See also: Glossary of contract bridge terms • Dealer: the player entitled to make the first call; so chosen by a draw of the cards or in , so designated by the to be played Contract bridge, or simply bridge, is a trick-taking game using a standard 52-card deck. It is played by • Opener: the first to make a bid four players in two competing partnerships,[1] with part- ners sitting opposite each other around a table.[2] Millions • Responder: partner of opener of people play bridge worldwide in clubs, tournaments, • online and with friends at home, making it one of the Intervenor: the first of the opponents to make a call world’s most popular card games, particularly among other than pass [3][4] seniors. The is the govern- • Overcaller: the first of the opponents to make a call ing body for international competitive bridge. other than pass or double The game consists of several deals[5] each progressing • Advancer: partner of intervenor; also, partner of through four phases: dealing the cards, the auction (also overcaller referred to as bidding), playing the cards, and scoring the results.[6] However, most club and tournament play in- • Declarer: the player who first bids the denomination volves some variant of duplicate bridge, where the cards of the ultimate contract are not re-dealt on each occasion, the same deal being played by two or more different sets of players to enable • Dummy: partner of declarer comparative scoring. • First seat: the dealer

• Second seat: the player next in clockwise rotation 1 Game play after the dealer • Third seat: the player next in clockwise rotation af- 1.1 Fundamentals and preliminaries ter the player in second seat • Fourth seat: the player next in clockwise rotation Scope after the player in third seat • Contract bridge has immense scope by virtue of the large seat or passout seat: the player who if he number of unique deals which are possible. The 52- passes would end the auction card deck can be distributed to the four players some • 28 [7] Opening leader: the player to the left of declarer; he 5.36×10 ways. In turn, each deal presents many op- makes the lead to the first trick tions on how it might be bid and played. • Left hand opponent (LHO): the player to one’s left

Players • Right hand opponent (RHO): the player to one’s right In its most basic form, bridge is a game played by four people in two teams of competing partnerships. For pur- Contracts and objectives poses of scoring and reference, each player is identified by one of the cardinal directions and thus North and [8] Contract bridge is a trick-taking card game where on each South play against East and West. More can participate, of several deals the opposing sides first compete in a bid- either as individuals or pairs or as teams of up to six, in ding auction for the right to establish the contract for that formal tournaments or social gatherings where the gov- deal, the side winning the auction being known as the erning rules of the event are prescribed by the sponsoring declaring side. The contract is an exchange of the right host. to establish which suit, if any, is trumps for an undertak- Additional designations for each of the four players may ing to win (at least) the number of tricks specified by the be used when referring to their actions during the auction highest bid. After the contract has been established, the or play of the cards: play of the cards proceeds as in most trick-taking card

1 2 1 GAME PLAY

games until all thirteen tricks have been played; at any pre-defined, depending only on the number of the board.) time during the play, one side may claim a stated number The scoring points that are won on a deal as a result of of the remaining tricks and concede the balance, if any. making a contract, and the points which are lost when Based on the actual number of tricks taken, the declar- failing to make a contract, are both significantly increased ing side will have either succeeded or failed in fulfilling for the side (partnership) that is vulnerable. Accordingly, the contract; if successful (known as making or to have whether one’s side is vulnerable affects one’s strategy for made), the declaring side scores points; if unsuccessful both bidding and play. (known as going down or being defeated), the defend- ing side scores points. The overriding objective is to win Variations the contest by accumulating more points than the oppo- nents. Although each variant of bridge has its own par- The most common contract bridge variations are rubber ticular scheme for awarding and accumulating points, all bridge and duplicate bridge. Variants within these two are based upon whether or not the contract for each deal types of contract bridge are numerous. was made or defeated and by how many tricks. See also: It can sometimes be advantageous to bid a contract that one does not expect to make and to be defeated, thus los- In rubber bridge, two partnerships participate in the game ing some points, rather than allow the opposing side to at one table and the objective is to score the most points bid and make a contract which would score them an even in the play of several hands. A rubber is a 'best-of-three' greater number of points. This is known as a sacrifice, contest and is completed when one side is first to have won and is not uncommon if both sides are contesting the fi- two games. The side which has accumulated the most nal contract. points and wins the rubber may or may not be the side to have won two games. While rubber bridge is played com- Card, suit and bid rankings petitively and for stakes, it is most often played socially and with less formality than duplicate bridge. In the standard 52-card deck used in bridge, the ace is ranked highest followed by the king, queen, and jack and See also: Duplicate bridge the spot-cards from the ten down through to the two. Suit denominations also have a rank order with notrump In duplicate bridge, the cards held by each player in each being highest followed by spades, hearts, diamonds and deal are preserved so that each partnership plays the same clubs. The two lower-ranked suits (diamonds and clubs) set of hands as their East-West or North-South counter- are called the minor suits and the higher-ranked suits parts at other tables and with the scoring based upon rel- (spades and hearts) are called the major suits. ative performance, thus emphasizing skill over chance. Bidding is based on the premise that the lowest contract While duplicate is the primary form of higher levels of available to bidders starts with the proposition to take competitive bridge, it is also played socially. seven tricks, i.e. one cannot contract to make less than seven tricks. Given this, the bidding is said to start at the 1.2 Dealing one-level when contracting for a total of seven tricks, at the two-level for eight tricks and so on to the seven-level to In rubber bridge, partnerships may be self-determined or contract to take all thirteen tricks. The six tricks required decided by a cut of the cards, the two highest cut playing as the base for any bid are referred to as the “book”. against the two lowest, and the first dealer is the player Within any level of bidding (i.e. from one to seven), suit cutting the highest card. The cards are shuffled before rank establishes the bid’s rank, i.e. a bid of two diamonds each deal, and the dealer deals the cards clockwise one outranks a bid of two clubs, a bid of three spades outranks at a time, starting with the left-hand opponent, so that a bid of three hearts, a bid of three notrump outranks a each player receives a hand of thirteen cards. The deal bid of three spades. Thus, there are 35 possible basic rotates clockwise each hand. In order to save time, a sec- contracts (five at each of the seven levels); 1♣ being the ond deck, preferably distinct from the first, is employed lowest, followed by 1♦ etc., up to 7NT, the highest pos- so that as the first is being dealt, the second is being shuf- sible bid. fled by the partner of the current dealer. When shuffled, the second deck is placed to the shuffler’s right, i.e. to the Vulnerability next dealer’s left. After the play and scoring of the hand has concluded, the deal is rotated and the second deck is A key feature of bridge is the concept of vulnerability. moved by the next dealer from his left to his right, cut On each deal, each side is said to be either vulnerable by the previous dealer and dealt; the partner of the new or not vulnerable depending upon whether or not it has dealer shuffles the first deck continuing the process. If won a game in the current rubber; if it has, the side is the auction is passed out, i.e. no bids are made and only said to be vulnerable; if it has not, it is said to be not vul- four passes are called, the hands are abandoned and the nerable. (In duplicate play, the sides’ vulnerabilities are turn to deal passes in rotation.[9] 1.3 Auction or bidding 3

ment play.[10] As the boards arrive for play at each sub- sequent table, the four players take their cards from the board and should count them to ensure that there are 13 cards in their hand before looking at the cards, so that any irregularity can be corrected before the auction and play commence. In some countries, the rules require that after the hand is played for the first time, the players write the hands down on the traveling scoresheet, which can be consulted later if the cards are accidentally mixed up. Alternatively, if the boards are pre-dealt, “curtain cards” may be supplied which have each hand printed on them, so that each player can check at the beginning of the deal that he has the right cards. Pre-dealt hands also have the advantage that, at the end of the session, diagrams of each deal can be made available to the players for later analysis.

1.3 Auction or bidding

See also: , and Bridge conventions

The auction is a bidding process undertaken within strict Rectangular aluminum board procedural and ethical protocols to determine the declar- ing side and the final contract. The contract is an un- dertaking to win at least the specified number of odd tricks[11] in the declared denomination.[12] Each partner- In duplicate bridge, the hands are shuffled and dealt only ship works jointly by means of various 'calls’ to secure once, at the beginning of the session. Players do not play a contract at the highest level deemed advisable by them their cards to the centre of the table during the play but given their card holdings. A call[13] is limited to a vocab- instead play them immediately in front of themselves and ulary of 38 words or phrases consisting of: turn them face down at the end of each trick. The direc- tion that each face down card is pointed indicates which • side won each trick, so that at the end of the hand, the a Bid which states a level and a denomination; given number of tricks taken by each side can be determined. 7 levels of bidding and 5 denominations, there are At the end of the hand each player returns his hand, intact, 35 possible bids to the correct slot in a bridge board such as that shown at • Double, when the previous call other than pass was right in which it is transported to other tables so that ev- a bid by an opponent eryone can play the same deals. The results for different players playing the same deal are then compared. This re- • Redouble, when the previous call other than pass was moves much of the element of chance from scores. It also a double by an opponent means that in the case of an irregularity or dispute over a • hand before the cards are returned to the board, they can Pass, when unwilling or unable to make one of the be reviewed and it can be determined who played which three preceding calls cards in what order. In some competitions, boards are pre-dealt prior to the In social games, the players may make their calls orally; competition, especially if the same hands are to be played otherwise, players use a containing cards for at many locations (for example in a large national or in- each possible call and place the respective card face up ternational tournament). Sometimes mechanical dealing on the table in front of their position. machines are used for pre-dealing hands at large tourna- The auction starts with the dealer and proceeds clockwise ments and in many clubs. Even for boards dealt or as- with each player, having first evaluated their hand, mak- sembled manually, computer software is often used to ing a call in order. During the auction, each bid must be generate the random distributions of hands. Before the 'sufficient', i.e. it must be higher than its predecessor. A widespread availability of computers, printed books of bid is sufficient if it specifies any denomination at a higher random deals could be purchased. In the past it was com- level than the last bid, or a higher-ranked[14] denomina- mon for uninteresting hands to be eliminated or replaced, tion at the same level. Thus, after a bid of 3♥, bids of 2♠ but this practice is now prohibited in sanctioned tourna- or 3♣ are not sufficient, but 3♠ or 4♦ are. 4 1 GAME PLAY

The auction continues until there are three consecutive assumed “book” of six, plus four as bid, with spades as passes not including the dealer’s first call. The partner- trumps), to make the contract and get a positive score. ship which makes the last bid then becomes the "declaring Success in this goal is rewarded by points in the scoring side" and is said to have 'won' the auction. The player on phase for the declarer’s side. If the declarer fails to make the declaring side who, during the auction, first stated the the contract, the defenders are said to have set or defeated denomination of the final bid becomes "declarer,” the de- the contract (declarer has gone down), and are awarded clarer’s partner becomes the "dummy,” and the opposing points for doing so. side become the “defenders.” The defender to the left of To begin play, the defender on the declarer’s left makes declarer must make the . the opening lead. In more formal play, the opening leader In addition to establishing the level and denomination of does so by first placing the card face down on the ta- the final contract,[15] the final contract may be doubled ble to afford his partner an opportunity to ask questions (by the opponents) or redoubled (by the declaring side about the auction, then faces it when partner has no fur- after the opponents had already doubled), in which case ther questions. This practice also allows the defender to the score for the hand is increased, whether the contract return the card to his hand without penalty if the lead is is made or defeated. not his to make. If all four players pass in the first round, the deal is not The dummy then spreads his hand on the table with each played; in rubber bridge the deal is not scored and the suit in a column from highest to lowest facing the de- turn to deal passes to the next player, while in duplicate clarer, customarily with any suit on declarer’s left the score is recorded as zero for each pair and returned to and the colors of the suits alternating. The rules of play the board. are similar to other trick-taking games, except that the declarer directs the play of cards from the dummy in ad- dition to playing cards from his own hand. Dummy is al- 1.3.1 Strategy lowed to try to prevent declarer from infringing the rules, but otherwise must not interfere with the play; for exam- The purpose of some early bids may be to exchange in- ple, dummy may attempt to prevent declarer from leading formation rather than to set the final contract. For most from the wrong hand (by stating, e.g., “you won the last players, many calls (bids, doubles and redoubles, and trick in dummy”) but must not comment on opponents’ sometimes even passes) are not made with the intention actions or make suggestions as to play. that they become the final contract, but to describe the strength and distribution of the player’s hand, so that the The hands play clockwise around the table, and each hand partnership can reach an informed conclusion on their must “follow suit” (that is, play a card of the suit lead to best contract, and/or to obstruct the opponents’ bidding. the trick) if able. A hand that cannot follow suit may ei- The set of agreements used by a partnership about the ther “ruff” (play a trump) if there is a trump suit or “sluff” meaning of each call is referred to as a bidding system, (play a card of any other suit). The hand that plays either full details of which must be made available to the oppo- the highest trump or, in a trick that contains no trumps, nents; 'secret' systems are not allowed. An opponent can the highest card of the suit led to the trick (1) wins the ask the bidder’s partner to explain the meaning of the call. trick for its side and (2) proceeds to lead to the next trick. The play continues until all thirteen tricks are played. The declarer or a defender may “claim” the rest of the tricks 1.3.2 Example by showing his hand and stating how he will take them. In rubber bridge, one player typically gathers the tricks for In the example at left, West was the dealer and first to bid. each side. In duplicate bridge, each player retains the card The bidding proceeded as shown with South becoming played from his hand to each trick and lays it on the table the declarer in a 4♠ contract, being the first to bid spades. turned in the direction of the side that won the trick, thus East-West become the defenders and West becomes the keeping the hands separate to return them to the board at opening leader, North becomes the dummy and spades the end of play. the trump suit. Ten tricks are required by North-South, the book plus the 4-level bid. Since East’s double of 2♦ If upon reviewing dummy after the opening lead, declarer was cancelled by the subsequent South’s 3♠ bid, it does assesses that he does not have enough tricks immediately not affect the contract. available to make his contract, he can try to develop addi- tional tricks through a variety of methods. These include:

1.4 Play of the cards • losing tricks to the defenders’ high cards in order to “promote” the remaining cards of that suit in his See also: Opening lead hand. • running out long suits after the defenders’ cards in The contract level sets a specific target: in the example that suit are exhausted, to force defenders to discard above, the declarer must attempt to win ten tricks (the useful cards. 5

• the "finesse", in which a low card is led toward a high • Every odd trick bid and made, known as contract card in the hope of trapping a high card held by the points defender who must play in between. • Each overtrick, i.e. each trick taken over the con- • in trump contracts, the declarer may attempt to tract level, known as overtrick points cover losers in his hand by trumping them in • dummy, while also taking care to draw out the de- Bonus points dependent upon the game variant be- fenders’ trumps if necessary. ing played for certain contract levels including part- game, game, small slam and grand slam contracts as • cutting communications between the two defenders, well as for winning the rubber for instance by allowing them to win early tricks in a • suit until they are unable to use the suit as an . Bonus points in some game variants for making a doubled or redoubled contract • more advanced techniques include the "squeeze • Bonus points in some game variants for holding four play" in which a defender is forced to choose which or more honors in one hand card to discard before declarer has to make his own discard choice. When the declarer fails to make the contract, the defend- ing side receives points for undertricks – the number of 1.5 Defense tricks by which declarer fell short of the goal. The various bonus structures give certain bid levels spe- Defense is the play of the cards by the non-declaring part- cial significance. For example, if the declarer takes all nership, with the goal of preventing the opponents achiev- thirteen tricks in a notrump contract, there is a large ing their contract. Bridge writer Edwin B. Kantar wrote score difference between contracts of 1NT and 7NT. The “There is no question that defense is the most difficult bonuses available for contracting at higher levels ensures [16] aspect of playing bridge.” competitiveness in the auction. The most important level Of particular importance is the first defensive move, the is game, which is any contract whose bid trick value is opening lead made by the player sitting left of the de- 100 or more points. Game level varies by suit, since dif- clarer. There is an extensive bridge literature on the ferent suits are worth different amounts in scoring. The choice of opening leads. As play proceeds, defending game level for notrump is three, the game level for hearts partners can try to convey information about their hands or spades (the major suits) is four, and the game level through various systems of signals. A higher card dis- for clubs or diamonds (the minor suits) is five. Because carded on a trick might, for example, encourage partner of the value of the game bonus, much of the bidding to continue leading that suit, whereas a lower card would revolves around investigating the possibility of making be discouraging. game. Additional bonuses are awarded for bidding and making small slam (level 6, i.e. 12 tricks) and grand slam Good defense is particularly dependent upon partnership (level 7, i.e. all 13 tricks) contracts. agreements and effective cooperation between the part- ners. As a result, longer-term partnerships tend to de- The concept of vulnerability affects scoring and intro- velop the most effective defensive play. duces a wider range of tactics in bidding and play. Every partnership is in one of two states: vulnerable or non- vulnerable, either by virtue of their previous deals in rub- 1.6 Scoring ber bridge or as predetermined by the board in duplicate bridge. When a pair is vulnerable, game and slam bonuses Main article: are higher, as are penalties for failure to make the con- tract. Finally, doubling and redoubling also has a signifi- cant effect on scoring, especially for vulnerable contract When play ends, the score is determined by comparing which are either defeated or which win overtricks. the number of tricks won by the declaring side to the num- ber required to satisfy the contract. The available scoring While the scoring of individual hands in rubber and points for the declaring side are dependent upon both the duplicate bridge share many features, the accumulation level and strain of the contract and are awarded to them of scores over several hands differs significantlly. See only when the contract is 'made', i.e. at least the con- bridge scoring for details and examples. tracted for number of tricks are won. If the declaring side fails to take the required number of tricks, defending side receives points instead for “setting” (or “defeating”) 2 Rules the contract. When the declarer makes the contract, the declarer’s side The rules of the game are referred to as the 'Laws’ as pro- receives points for: mulgated by various bridge organizations. 6 3 HISTORY

2.1

Main article: Laws of Duplicate Bridge

The official rules of duplicate bridge are promulgated by the World Bridge Federation (WBF) as the “International Code of Laws of Duplicate Bridge, 2007”.[17] The Laws Committee of the WBF, composed of world experts, up- dates the Laws every 10 years; it also issues a Laws Com- mentary advising on interpretations it has rendered. In addition to the basic rules of play, there are many ad- ditional rules covering playing conditions and the recti- fication of irregularities which are primarily for use by Bridge club at Shimer College, 1942. tournament directors who act as referees and have over- all control of procedures during competitions. In addi- tion, some details of procedure are left to the discretion Biritch, or Russian Whist by John Collinson. It and his of the zonal bridge organisation for tournaments under subsequent letter to The Saturday Review dated May 28, their aegis and some (for example, the choice of move- 1906, document the origin of Biritch as from the Rus- ment) to the sponsoring organisation (e.g. the club). sian community in Constantinople[24] and having some The zonal organisations of the WBF also publish edi- features in common with Solo Whist. The game had tions of the Laws. For example, the American Con- many significant bridge-like developments: dealer chose tract Bridge League publishes “Laws of Duplicate Bridge, the trump suit, or nominated his partner to do so; there 2008”,[18] “Laws of Contract Bridge, 2003”[19] and addi- was a call of notrumps (biritch); dealer’s partner’s hand tional supporting documentation including: Director De- became dummy; points were scored above and below cisions, Tech Files and Casebook (appeals from national the line; game was 3NT, 4H and 5D (although 8 club bridge championships).[20] odd tricks and 15 spade odd tricks were needed); the score could be doubled and redoubled; and there were slam bonuses. This game, and variants of it known as 2.2 Rules of rubber bridge “bridge”[25] and “bridge-whist”,[26] became popular in the United States and the UK in the 1890s despite the long- There are no universally accepted rules for rubber bridge established dominance of whist.[27] promulgated by bridge governing bodies; instead local In 1904 was developed, in which the play- rules such as The Laws of Contract Bridge as published by ers bid in a competitive auction to decide the contract and the American Contract Bridge League constitute the rules declarer. The object became to make at least as many for those wishing to abide by a published standard.[21] tricks as were contracted for and penalties were intro- The majority of rules mirror those of duplicate bridge in duced for failing to do so. the bidding and play and differ primarily in procedures The modern game of contract bridge was the result of for dealing and scoring. innovations to the scoring of auction bridge made by Harold Stirling Vanderbilt and others. The most signifi- 2.3 Laws of online play cant change was that only the tricks contracted for were scored below the line toward game or a slam bonus, a In 2001, the World Bridge Federation promulgated a set change that resulted in bidding becoming much more of Laws for online play.[22] challenging and interesting. Also new was the concept of “vulnerability”, making sacrifices to protect the lead in a rubber more expensive. The various scores were ad- justed to produce a more balanced and interesting game. 3 History Vanderbilt set out his rules in 1925, and within a few years contract bridge had so supplanted other forms of the game Main article: History of contract bridge that “bridge” became synonymous with “contract bridge.” Bridge is a member of the family of trick-taking games In the USA, most of the bridge played today is duplicate and is a development of Whist, which had become the bridge, which is played at clubs, in tournaments and on- dominant such game enjoying a loyal following for cen- line. In the UK, rubber bridge is still popular in both turies. According to the Oxford English Dictionary, homes and clubs, as is duplicate bridge. The number of Bridge is the English pronunciation of a game called people playing contract bridge has declined since its peak Biritch, which was also known as Russian Whist. in the 1940s, when a survey found it was played in 44% The oldest known Biritch rule book[23] dated 1886 is of US households. The game is still played, especially 4.1 Bidding boxes and bidding screens 7

amongst retirees, and in 2005 the ACBL estimated there the Laws (each ten years, next in 2017) and conduct world were 25 million players in the US.[28] championships.[30]

4.1 Bidding boxes and bidding screens 4 Tournaments

Bridge is a game of skill played with randomly dealt cards, which makes it also a game of chance, or more ex- actly, a tactical game with inbuilt randomness, imperfect knowledge and restricted communication. The chance element is in the deal of the cards; in competitions and clubs the chance element is largely eliminated by compar- ing results of multiple pairs in identical situations. This is achievable when there are eight or more players, sitting at two or more tables, and the deals from each table are preserved and passed to the next table, thereby duplicat- ing them for the next table of participants to play. At the end of a session, the scores for each deal are compared, and the most points are awarded to the players doing the best with each particular deal. This measures skill be- Bidding box cause each player is being judged only on the ability to bid with, and play, the same cards as other players. However In tournaments, "bidding boxes" are frequently used, as very often even the most skillful play will only succeed noted above. In top national and international events, some of the time, and the skilled player may be unlucky "bidding screens" are used. These are placed diagonally because an alternative, less expert play achieves a better across the table, preventing partners from seeing each result. But in the long run the expert player will score other during the game; often the is removed af- better. ter the auction is complete. This form of the game is referred to as duplicate bridge and is played in clubs and tournaments, which can gather as many as several hundred players. Duplicate bridge is a 5 Game strategy mind sport, and its popularity gradually became compa- rable to that of chess, with which it is often compared for its complexity and the mental skills required for high-level 5.1 Bidding competition. Bridge and chess are the only “mind sports” recognized by the International Olympic Committee, al- Main articles: Bidding system and though they were not found eligible for the main Olympic program.[29] Much of the complexity in bridge arises from the diffi- culty of arriving at a good final contract in the auction. The basic premise of duplicate bridge had previously been used for whist matches as early as 1857. Initially, This is a difficult problem: the two players in a part- nership must try to communicate sufficient information bridge was not thought to be suitable for duplicate com- petition; it wasn't until the 1920s that (auction) bridge about their hands to arrive at a makeable contract, but the information they can exchange is restricted – information tournaments became popular. may be passed only by the calls made and later by the In 1925 when contract bridge first evolved, bridge tourna- cards played, not by other means; in addition, the agreed- ments were becoming popular, but the rules were some- upon meaning of each call and play must be available to what in flux, and several different organizing bodies the opponents. were involved in tournament sponsorship: the American Bridge League (formerly the American Auction Bridge Since a partnership that has freedom to bid gradually at League, which changed its name in 1929), the American leisure can exchange more information, and since a part- Whist League, and the United States Bridge Association. nership that can interfere with the opponents’ bidding (as In 1935, the first officially recognized world champi- by raising the bidding level rapidly) can cause difficul- onship was held. By 1937, however, the American Con- ties for their opponents, bidding systems are both infor- tract Bridge League had come to power (a union of the mational and strategic. It is this mixture of information ABL and the USBA), and it remains the principal orga- exchange and evaluation, deduction, and tactics that is at nizing body for bridge tournaments in North America. In the heart of bidding in bridge. 1958, the World Bridge Federation was founded to pro- A number of basic rules of thumb in bridge bidding and mote bridge world-wide, coordinate periodic revision to play are summarized as . 8 5 GAME STRATEGY

5.1.1 Bidding systems and conventions substantial bidding room before a possibly strong oppos- ing pair can identify whether they have a good possibil- A bidding system is a set of partnership agreements on ity to play the hand, or in what suit or at what level they the meanings of bids. A partnership’s bidding system is should do so. Several systems include the use of opening usually made up of a core system, modified and com- bids or other early bids with weak hands including long plemented by specific conventions (optional customiza- (usually six to eight card) suits at the 2, 3 or even 4 or 5 tions incorporated into the main system for handling spe- levels as . cific bidding situations) which are pre-chosen between the partners prior to play. The line between a well-known 5.1.2 Basic natural systems convention and a part of a system is not always clear-cut: some bidding systems include specified conventions by default. Bidding systems can be divided into mainly nat- As a rule, a natural suit bid indicates a holding of at least ural systems such as and , and four (or more, depending on the situation and the sys- mainly artificial systems such as the and tem) cards in that suit as an opening bid, or a lesser num- Strong Diamond (see Strong Diamond). ber when supporting partner; a natural NT bid indicates a . Calls are usually considered to be either natural or con- ventional (artificial). A natural bid is one in which the Most systems use a count of high card points as the basic evaluation of the strength of a hand, refining this by refer- suit and level bid is essentially passing the information “I have some cards in this suit and (usually) some high cards ence to shape and distribution if appropriate. In the most commonly used point count system, aces are counted as 4 in my hand"; a natural double says in effect “I don't think the opponents can make their contract, so I want to raise points, kings as 3, queens as 2, and jacks as 1 point; there- fore, the deck contains 40 points. In addition, the distri- the stakes”. By contrast, a conventional (artificial) call of- fers and/or asks for information by means of pre-agreed bution of the cards in a hand into suits may also contribute coded interpretations, in which some calls convey very to the strength of a hand and be counted as distribution specific information or requests that are not part of the points. A better than average hand, containing 12 or 13 natural meaning of the call. Thus in response to 4NT, a points, is usually considered sufficient to open the bid- 'natural' bid of 5♦ would state a preference towards a di- ding, i.e., to make the first bid in the auction. A combi- amond suit or a desire to play the contract in 5 diamonds, nation of two such hands (i.e., 25 or 26 points shared be- whereas if the partners have agreed to use the common tween partners) is often sufficient for a partnership to bid, , a bid of 5♦ in the same situa- and generally to make, game in a or notrump tion would say nothing about the diamond suit, but tell (more are usually needed for a game, as the the partner that the hand in question contains exactly one level is higher). ace. In natural systems, a 1NT opening bid usually reflects a Conventions are valuable in bridge because of the need to hand that has a relatively balanced shape (usually between pass information beyond a simple like or dislike of a par- two and four (or less often five) cards in each suit) and a ticular suit, and because the limited bidding space can be sharply limited number of high card points, usually some- where between 12 and 18 – the most common ranges use used more efficiently by taking situations in which a given call will have less utility, because the information it would a span of exactly three points, (e.g., 12-14, 15-17 or 16- 18), but some systems use a 4 point range, usually 15-18. convey is not valuable or because the desire to convey that information would arise only rarely, and giving that call Opening bids of 3 or higher are preemptive bids, i.e., bids an artificial meaning that conveys more useful (or more made with weak hands that especially favor a particular frequently useful) information. There are a very large suit, opened at a high level in order to define the hand’s number of conventions from which players can choose; value quickly and to frustrate the opposition. For ex- many books have been written detailing bidding conven- ample, a hand of ♠ KQJ9872 ♥ 7 ♦ 42 ♣ 763 would tions. Well-known conventions include Stayman (to ask be a candidate for an opening bid of 3♠, designed to for the showing of any 4 card major suit in a 1NT opener’s make it difficult for the opposing team to bid and find hand), Jacoby transfers (a request by the weak hand for their optimum contract even if they have the bulk of the the stronger partner to bid a particular suit first, and there- points, as it is nearly valueless unless spades are trumps, fore to become the declarer), and the Blackwood conven- it contains good enough spades that the penalty for being tion (to ask for information on the number of aces and set should not be higher than the value of an opponent kings held, used in slam bidding situations). game, and the high card weakness makes it more likely The term refers to a high level tactical bid by a that the opponents have enough strength to make game weak hand, relying upon a long suit rather than high-value themselves. cards for tricks. Preemptive bids serve a double purpose Openings at the 2 level are either unusually strong (2NT, – they allow players to indicate they are bidding on the natural, and 2♣, artificial) or preemptive, depending on basis of a long suit in an otherwise weak hand, which is the system. Unusually strong bids communicate an espe- important information to share, and they also consume cially high number of points (normally 20 or more) or a 5.1 Bidding 9

high trick-taking potential (normally 8 or more). opening hand lacking a notable heart or spade suit

Opening bids at the one level are made with hands con- • Whether opening bids at the two level are 'strong' taining 12–13 points or more and which are not suitable (20+ points) or 'weak' (i.e., pre-emptive with a 6 for one of the preceding bids. Using Standard Ameri- card suit). (Note: an opening bid of 2♣ is usually can with 5-card majors, opening hearts or spades usually played in otherwise natural systems as conventional, promises a 5-card suit. Partnerships who agree to play signifying any exceptionally strong hand) 5-card majors open a minor suit with 4-card majors and then bid their major suit at the next opportunity. This • Blackwood (either the original version or Roman Key means that an opening bid of 1♣ or 1♦ will sometimes Card) be made with only 3 cards in that suit. • Stayman (together with Blackwood, described as Doubles are sometimes given conventional meanings in “the two most famous conventions in Bridge”.[31]) otherwise mostly natural systems. A natural, or penalty double, is one used to try to gain extra points when the de- • Whether the partnership will play Jacoby transfers fenders are confident of setting (defeating) the contract. (bids of 2♦ and 2♥ over 1NT or 3♦ and 3♥ over The most common example of a conventional double is 2NT respectively require the 1NT or 2NT bidder to the of a low-level suit bid, implying sup- rebid 2♥ and 2♠ or 3♥ and 3♠), minor suit trans- port for the unbid suits or the unbid major suits and asking fers (bids of 2♠ and either 2NT or 3♣ over 1NT partner to choose one of them. respectively require the 1NT bidder to bid 3♣ and 3♦) and Texas transfers (bids of 4♦ and 4♥ respec- tively require the 1NT, or 2NT bidder to rebid 4♥ 5.1.3 Variations on the basic themes and 4♠)

Bidding systems depart from these basic ideas in vary- • What types of cue bids (e.g. rebidding the opponents’ ing degrees. Standard American, for instance, is a col- suit) the partnership will play, if any. lection of conventions designed to bolster the accuracy and power of these basic ideas, while Precision Club is a • Whether doubling a contract at the 1, 2 and some- system that uses the 1♣ opening bid for all or almost all times higher levels signifies a belief that the oppo- strong hands (but sets the threshold for “strong” rather nents’ contract will fail and a desire to raise the lower than most other systems – usually 16 high card stakes (a penalty double), or an indication of strength points) and may include other artificial calls to handle but no biddable suit coupled with a request that part- other situations (but it may contain natural calls as well). ner bid something (a takeout double). Many experts today use a system called 2/1 game forc- • Whether doubling or overcalling over opponents’ ing (enunciated as two over one game forcing), which 1NT is natural or conventional. Most common arti- amongst other features adds some complexity to the treat- ficial agreement is Cappelletti, where 2♣ is a trans- ment of the one notrump response as used in Standard fer to be passed or corrected to a major, 2♦ means American. In the UK, Acol is the most common system; both majors and a major shows that suit plus a mi- its main features are a weak one notrump opening with nor. 12-14 high card points and several variations for 2-level openings. • How the partnership’s bidding practices will be var- There are also a variety of advanced techniques used for ied if their opponents intervene or compete. hand evaluation. The most basic is the • Which (if any) bids are forcing and require a re- point count, (the 4-3-2-1 system detailed above) but this sponse. is sometimes modified in various ways, or either aug- mented or replaced by other approaches such as losing trick count, , , or Zar Within play, it is also commonly agreed what systems of Points. opening leads, signals and discards will be played: Common conventions and variations within natural sys- • tems include: Conventions for the opening lead govern how the first card to be played will be chosen and what it will mean, • Point count required for 1 NT opening bid ('mini' 10-12, 'weak' 12-14, 'strong' 15-17 or 16-18) • Signals indicate how cards played within a suit are • Whether an opening bid of 1♥ and 1♠ requires a chosen – for example, playing a noticeably high card minimum of 4 or 5 cards in the suit (4 or 5 card when this would not be expected can encour- majors) agement to continue playing the suit, and a low card can signal discouragement and a desire for partner to • Whether 1♣ (and sometimes 1♦) is 'natural' or 'sus- choose some other suit. (Some partnerships use “re- pect' (also called 'phoney' or 'short'), signifying an verse” signals, meaning that a noticeably high card 10 6 EXAMPLE

discourages that suit and a noticeably low card en- bidding. Alternatively, many partnerships play this same courages that suit, thus not “wasting” a potentially bidding sequence as “Crawling Stayman” by which the useful intermediate card in the suit of interest.) responder shows a weak hand (less than eight high card points) with shortness in diamonds but at least four hearts • Discards cover the situation when a defender cannot and four spades; the opening bidder may correct to spades follow suit and therefore has free choice what card if that appears to be the better contract. to play or throw away. In such circumstances the thrown-away card can be used to indicate some as- The situations detailed here are extremely simple exam- pect of the hand, or a desire for a specific suit to be ples; many instances of advanced bidding involve specific played. agreements related to very specific situations and subtle inferences regarding entire sequences of calls. • Count signals cover the situation when a defender is following suit (usually to a suit that the declarer has led). In such circumstances the order in which a de- 5.2 Play techniques fender plays his spot cards will indicate whether an even or odd number of cards was originally held in Main article: List of play techniques (bridge) that suit. This can help the other defender count out the entire original distribution of the cards in that Terence Reese, a prolific author of bridge books, points suit. It is sometimes critical to know this when de- out that there are only four ways of taking a trick by force, fending. two of which are very easy: • Suit preference signals cover the situation where a defender is returning a suit which will be ruffed by • playing a high card that no one else can beat his partner. If he plays a high card he is showing an entry in the higher side suit and vice versa. There are • trumping an opponent’s high card some other situations where this tool may be used. • establishing long suits (the last cards in a suit will • Surrogate signals cover the situation when it is criti- take tricks if the opponents don't have the suit and cal to show length in a side suit and it will be too late are unable to trump) if defenders wait till that suit is played. Then, the • play in the first declarer played suit is a count signal playing for the opponents’ high cards to be in a par- regarding the critical suit and not the trump suit it- ticular position (if their ace is to the right of your self. In fact, any signal made about a suit in another king, your king may be able to take a trick, espe- suit might be called as such. cially if, when that suit is led, the player to your right has to play their card before you do)

5.1.4 Advanced bidding techniques Nearly all trick-taking techniques in bridge can be re- duced to one of these four methods. The optimum play Every call (including “pass”, also sometimes called “no of the cards can require much thought and experience and bid”) serves two purposes. It confirms or passes some in- is the subject of whole books on bridge. formation to a partner, and also denies by implication any other kind of hand which would have tended to support an alternative call. For example, a bid of 2NT immediately after partner’s 1NT not only shows a balanced hand of 6 Example a certain point range, but also would almost always deny possession of a five-card major suit (otherwise the player The cards are dealt as shown in the bridge hand diagram; would have bid it) or even a four card major suit (in that North is the dealer and starts the auction which proceeds case, the player would probably have used the Stayman as shown in the bidding table. convention). As neither North nor East have sufficient strength to open Likewise, in some partnerships the bid of 2♥ in the se- the bidding, they each pass, denying such strength. South, quence 1NT - 2♣ - 2♦ - 2♥ between partners (opponents next in turn, opens with the bid of 1♥, which denotes passing throughout) explicitly shows five hearts but also a reasonable heart suit (at least 4 or 5 cards long, de- confirms four cards in spades: the bidder must hold at pending on the bidding system) and at least 12 high card least five hearts to make it worth looking for a heart fit points. On this hand, South has 14 high card points. West after 2♦ denied a four card major, and with at least five with 1♠, since he has a long spade suit of rea- hearts, a Stayman bid must have been justified by hav- sonable quality and 10 high card points (an can ing exactly four spades, the other major (since Stayman be made on a hand that is not quite strong enough for (as used by this partnership) is not useful with anything an opening bid). North supports partner’s suit with 2♥, except a four card major suit).[32] Thus an astute partner showing heart support and about 6-8 points. East sup- can read much more than the surface meaning into the ports spades with 2♠. South inserts a of 3♣, 11

inviting the partner to bid the game of 4♥ with good club from South’s hand and the queen will win anyway, this support and overall values. North complies, as North is at being the essence of the finesse). The game is now safe: the higher end of the range for his 2♥ bid, and has a fourth South ruffs a small club with a dummy’s trump, then ruffs trump (the 2♥ bid promised only three), and the dou- a diamond in hand for an entry back, and ruffs the last club bleton queen of clubs to fit with partner’s strength there. in dummy (sometimes described as a crossruff). Finally, (North could instead have bid 3♥, indicating not enough South claims the remaining tricks by showing his or her strength for game, asking South to pass and so play 3♥.) hand, as it now contains only high trumps and there’s no In the auction, North-South are trying to investigate need to play the hand out to prove they are all winners. whether their cards are sufficient to make a game (ten (The trick-by-trick notation used above can be also ex- tricks in hearts or spades, 11 tricks in clubs or diamonds), pressed in tabular form, but a textual explanation is usu- which yields bonus points if bid and made. East-West are ally preferred in practice, for reader’s convenience. Plays competing in spades, hoping to play a contract in spades of small cards or discards are often omitted from such a at a low level. 4♥ is the final contract, 10 tricks being description, unless they were important for the outcome). required for N-S to make with hearts as trump. North-South score the required 10 tricks, and their oppo- South is the declarer, having been first to bid hearts, and nents take the remaining three. The contract is fulfilled, the player to South’s left, West, has to choose the first and North enters the pair numbers, the contract, and the card in the play, known as the opening lead. West chooses score of +420 for the winning side (North is in charge of the spade king because spades is the suit the partnership bookkeeping in duplicate tournaments) on the traveling has shown strength in, and because they have agreed that sheet. North asks East to check the score entered on the when they hold two touching honors (or adjacent honors) traveller. All players return their own cards to the board, they will play the higher one first. West plays the card and the next deal is played. face down, to give their partner and the declarer (but not On the prior hand, it is quite possible that the ♣K is held dummy) a chance to ask any last questions about the bid- by West. For example, by swapping the ♣K and ♥A be- ding or to object if they believe West is not the correct tween the defending hands. Then the 4♥ contract would hand to lead. After that, North’s cards are laid on the table fail by one trick (unless West had led a club early in the and North becomes dummy, as both the North and South play). However the failure of the contract would not mean hands will be controlled by the declarer. West turns the that 4♥ is a bad contract on this hand. The contract de- lead card face up, and the declarer studies the two hands pends on the club finesse working, or a mis-defense. The to make a plan for the play. On this hand, the trump ace, a bonus points awarded for making a game contract far out- spade, and a diamond trick must be lost, so declarer must weigh the penalty for going one off, so it is best strategy not lose a trick in clubs. in the long run to bid game contracts such as this one. If the ♣K is held by West, South will find it very hard Similarly, there is a minuscule chance that the ♣K is to prevent it making a trick (unless West leads a club). in the west hand, but the west hand has no other clubs. However, there is an almost-equal chance that it is held In that case, declarer can succeed by simply cashing the by East, in which case it can be 'trapped' against the ace, ♣A, felling the ♣K and setting up the ♣Q as a winner. and will be beaten, using a tactic known as a finesse. However the chance of this is far lower than the simple After considering the cards, the declarer directs dummy chance of approximately 50% that East started with the (North) to play a small spade. East plays low (small card) ♣K. Therefore the superior is to take the and South takes the ♠A, gaining the lead. (South may club finesse, as described above. also elect to , but for the purpose of this example, let us assume South wins the ♠A at trick 1). South proceeds by drawing trump, leading the ♥K. West decides there 7 is no benefit to holding back, and so wins the trick with the ace, and then cashes the ♠Q. For fear of conceding a ruff and discard, West plays the ♦2 instead of another Main article: Computer bridge spade. Declarer plays low from the table, and East scores the ♦Q. Not having anything better to do, East returns the remaining trump, taken in South’s hand. The trumps now accounted for, South can now execute the finesse, 7.1 User-based play perhaps trapping the king as planned. South enters the dummy (i.e. wins a trick in the dummy’s hand) by leading After many years of little progress, computer bridge a low diamond, using dummy’s ♦A to win the trick, and made great progress at the end of the 20th century. In leads the ♣Q from dummy to the next trick. East covers 1996, the American Contract Bridge League (ACBL) ini- the queen with the king, and South takes the trick with the tiated official World Championships Computer Bridge, ace, and proceeds by cashing the remaining master ♣J. (If to be held annually along with a major bridge event. East doesn't play the king, then South will play a low club The first Computer Bridge Championship took place in 1997 at the North American Bridge Championships in 12 7 COMPUTER BRIDGE

Albuquerque, New Mexico. Australian Bridge Federation. MSN and Yahoo! Games Strong bridge playing programs such as Jack (World have several online rubber bridge rooms. In 2001, World Champion in 2001, 2002, 2003, 2004, 2006 and 2009), Bridge Federation issued a special edition of the lawbook Wbridge5 (World Champion in 2005, 2007 and 2008), adapted for internet and other electronic forms of the RoboBridge[33] and many-time finalist Bridge Baron, game. would probably rank among the top few thousand human Advantages of online play include: pairs worldwide. A series of articles published in 2005 and 2006 in the Dutch IMP describes • The software prevents improper plays and calls, such matches between Jack and seven top Dutch pairs. A to- as insufficient bids, (failure to follow suit tal of 196 boards were played. Overall, the program Jack when able), and actions out of turn. lost, but by a small margin (359 versus 385 imps). • Unauthorised information cannot be passed by tone of voice or body language (but can much more easily 7.2 Internet-based play be passed by external communication).

There are several free and subscription-based services • Detailed records are kept which can aid partners to available for playing bridge on the internet. For exam- review and improve their bidding and play. ple: • Hands can be easily be analysed for best play (double • OKbridge[34] is the oldest of the still-running inter- dummy) afterwards. net bridge services: was established as a commer- • cial enterprise in 1994, but the program started to Can play with partners far away - or across town. be used interactively in August 1990 on players of • No need to assemble 4 people in one place. all standards. Beginners to world class may be found [35] playing there. OKbridge is a subscription-based • Faster play - no shifting chairs or waiting for shuffles. club, with services such as customer support and ethics reviews. • Player rating systems may attempt to measure ability without regard to the number of games played or the • The subscription-based online Bridge Club Live number of years spent accumulating . (BCL),[36] founded in 1994. Calling itself “the friendliest Bridge club of the world”, BCL organizes • Fewer restrictions on the conventions that are per- annual 4–6 day meetings, in a different country each mitted compared to club tourneys. year, to get its members together. • Easy to find opponents for practice in bidding and • SWAN Games[37] was founded April, 2000. In playing. March 2004, announced a partnership to provide in- ternet services to SBF members and is a competitor • [35] You will meet bridge players from every country and in subscription-based online bridge clubs. time zone. • Bridge Base Online (BBO) is the most active on- • Flexibility when to play (24/7), and choice of oppo- line bridge club in the world, with more than 100 nent skill level. 000 daily connections and 500 000 hands played [35] each day. in part because it is free to play reg- • Choice of individual, pairs, or team competitions. ular games and volunteer-run tournaments. • Fun to watch famous bridge stars play “live” as well These and other sites offer various features, such as op- as well-known personalities such as Bill Gates and portunities to earn ACBL masterpoints, to play in on- Warren Buffett (who used to appear regularly on line tournaments, to compile lists of friends, and to earn OKBridge in set games) money playing Bridge. Bridge Base Online also has a feature showing tournaments from around the There are also a number of disadvantages: world for anyone interested to watch live. As well as writ- ten commentaries from top level players, voice commen- taries have been incorporated since mid-2011. Software • Inability to decide on bidding convention ahead of and hardware has been tested in 2011 in order to have time when partners are strangers. digital cameras recognize the cards being played, which • will avoid human error or delay. A reduced social element. Some national contract bridge organizations now offer • Players may leave before a hand finishes, or in the online bridge play to their members, including the En- middle of a planned session, either intentionally or glish Bridge Union, the and the because of connection difficulties. 10.1 Notes 13

Tournaments are usually shorter online. A common [15] ; (June 2008). Beginning length is 12 boards(deals). Online services support many Bridge. . pp. 7–. ISBN 978-1-897106- simultaneous tournaments. When you finish one tourna- 33-4. Retrieved 20 August 2010. ment, another will start soon. [16] Kantar, Edwin B. Introduction to Defender’s Play, Melvin Some online services like BBO have apps for Android and Powers Wiltshire Book Company, 1968. Introduction iPhone. [17] “World Bridge Federation Laws of Duplicate Bridge”. Worldbridge.org. Retrieved 2011-11-05. 8 Card games related to bridge [18] ACBL Laws of Duplicate Bridge, 2008. Requirements for convention charts, alerts, and other laws are also available 9 See also at the ACBL website. [19] ACBL Laws of Contract Bridge, 2003. 10 References [20] A cross-referenced listing including documentation is available at the BridgeHands website. 10.1 Notes [21] Laws of Contract Bridge, ACBL official site. [1] Reese, Terence (1980). Bridge. Teach Yourself Books. Hodder and Stoughton. ISBN 0-340-32438-4., page 1. [22] World Bridge Federation Laws of Electronic Bridge, 2001 for online play. [2] In face-to-face games, a convenient table size is from 32 to 40 inches (80 to 100 centimeters) square or a round [23] “Alternate source for Biritch, or Russian Whist by John table allowing each player to reach to the center of the Collinson, 1886”. Pagat.com. Retrieved 2011-11-05. table during the play of the cards. In online computer play, players from anywhere in the world sit at a virtual table. [24] Depaulis, Thierry; Fuchs, Jac (Sep–Oct 2003). First Steps [3] USA Today: Billionaires bank on bridge to trump poker of Bridge in the West: Collinson’s 'Biritch'. The Playing- Card, Vol. 32, No. 2.pp. 67-76. [4] New York Times: At the Bridge Table, Clues to a Lucid Old Age [25] (Elwell 1905 and Benedict 1900) [5] The terms deal, hand and board may be used interchange- ably in bridge literature. More accurately, a hand is one [26] (Melrose 1901) player’s holding of 13 cards, a deal is the four hands in one allocation of 52 cards; a board is a term more applicable [27] (Foster 1889) to duplicate bridge and refers to a deal. [28] Turning Tricks – The rise and fall of contract bridge” The [6] Kantar, Eddie (2006). Bridge for Dummies, 2nd Edition. New Yorker, September 17, 2007 Wiley Publishing, Inc. ISBN 978-0-471-92426-5., page 11. [29] “Review of the Olympic programme and the recommen- dations on the programme of the games of the XXIX [7] Manley et al. (2011), p. 579. This number is expressed Olympiad, Beijing 2008; page 8”. October 2011. as 53.6 octillion.

[8] Francis et al. 2001, p. 81. See COMPASS POINTS. [30] Francis et al. 2001, p. 576. See WORLD BRIDGE FED- ERATION (WBF). [9] Law 22(a) of the Laws of Contract Bridge, ACBL official site. [31] Bridge Lessons series, Stayman & Transfer (Deal 1), by [10] Computers Deals at the BridgeHands web site. See also Computer-Dealt Hands at the ACBL website. [32] Taken from Andrew Robson Bridge Lessons series, “Stay- [11] Odd tricks refers to the tricks beyond the first six. Ac- man & Transfer”, deal 14 cordingly, the number of odd tricks bid can range from 1 to 7 inclusive. [33] “RoboBridge”. RoboBridge. 2011-10-22. Retrieved 2011-11-05. [12] Denomination refers to one of the suits (spades, hearts, diamonds or clubs) or to notrump. [34] OKbridge website [13] Although both are technically incorrect, the word “bid” is often used informally in place of “call” and “suit” may [35] Manley et al. (2011), p. 597 occasionally imply inclusion of “notrump” [36] Bridge Club Live website [14] Notrump ranking the highest, followed by spades, hearts, diamonds, and clubs. [37] Swan Games website 14 12 EXTERNAL LINKS

10.2 Bibliography

• Francis, Henry G., Editor-in-Chief; Truscott, Alan F., Executive Editor; Francis, Dorthy A., Editor, Sixth Edition (2001). The Official Encyclopedia of Bridge (6th ed.). Memphis, TN: American Con- tract Bridge League. ISBN 0-943855-44-6. OCLC 49606900.

• Manley, Brent, Editor; Horton, Mark, Co-Editor; Greenberg-Yarbro, Tracey, Co-Editor; Rigal, Barry, Co-Editor (2011). The Official Encyclope- dia of Bridge (7th ed.). Horn Lake, MS: American Contract Bridge League. ISBN 978-0-939460-99- 1.

11 Further reading

Further information: List of bridge books

12 External links

• American Contract Bridge League (ACBL) • New Zealand Contract Bridge Association (NZCBA)

• World Bridge Federation (WBF) 15

13 Text and image sources, contributors, and licenses

13.1 Text

• Contract bridge Source: http://en.wikipedia.org/wiki/Contract%20bridge?oldid=646850742 Contributors: Magnus Manske, TwoOneTwo, Derek Ross, CYD, Tarquin, Koyaanis Qatsi, Jeronimo, DanKeshet, Andre Engels, Eclecticology, Danny, XJaM, Ortolan88, Space Cadet, SimonP, Marknau, Camembert, Youandme, Robert Dober, Smelialichu, Michael Hardy, Pit, Stormwriter, Liftarn, Stephen C. Carlson, SGBailey, Kosebamse, Docu, Kingturtle, Darkwind, Glenn, Rob Hooft, Charles Matthews, Timwi, Jay, Tpbradbury, Nv8200p, VeryVerily, Rls, Carlossuarez46, Josh Cherry, Tomchiukc, Altenmann, Mirv, Puckly, Smb1001, Sunray, Hadal, Wxlfsr, Cutler, Decrypt3, Centrx, Gwalla, JamesMLane, Smjg, DocWatson42, Achurch, Laudaka, Elf, Wwoods, Lefty, Fleminra, Niteowlneils, Radius, Eequor, JillandJack, Pne, Telso, CryptoDerk, John Foley, Bumm13, Icairns, Eranb, B.d.mills, Klemen Kocjancic, Ulmanor, Spiffy sperry, Poccil, Duja, Guanabot, FT2, Cacycle, LindsayH, Paul August, ESkog, MisterSheik, 2005, Jpgordon, Yono, Giraffedata, Haham hanuka, Lexw, Martin S Taylor, Grutness, Visviva, Buoren, Harm.frielink, Drbreznjev, DarkNight, Dienstag, Mindmatrix, Csnydermvpsoft, Percy Snoodle, Uncle G, Robert K S, Duncan.france, Tabletop, Mangojuice, Estienne, Graham87, Tim!, Bubba73, DoubleBlue, Bearfoot, RexNL, Nicapicella, Alphachimp, DVdm, Dj Capricorn, Borgx, Hairy Dude, Hede2000, Casey56, Mightypile, Nfu-peng, Gaius Cornelius, Schoen, Dtrebbien, JocK, Rbarreira, Ospalh, T-rex, Dddstone, Xpclient, Cjs, Cambion, Ninly, Sharkb, Duefiori, Kevin, Rdhs100, Aliza250, EJSawyer, SmackBot, FocalPoint, KnowledgeOfSelf, Nickst, Hardyplants, Jcbarr, Drkarthi, Gilliam, Chris the speller, Thumperward, Jerome Charles Potts, Portnadler, Sgt Pinback, NYKevin, Can't sleep, clown will eat me, HoodedMan, Terryeo, Dreadstar, Timothy N. Hill, Maelnuneb, Jason S. Klepp, SashatoBot, BillFlis, PRRfan, Zapvet, Atakdoug, Mguppy, ALife, StuHarris, Colonel Warden, BPeppers1168, PKYip, ErWenn, Hyperman 42, JoannaSerah, Valoem, FabV, Owen214, Dewatf, Patrick Berry, Insanephantom, Dgw, Chmee2, JAWolf, Cydebot, Bkessler23, O. Harris, Ryan, Kjs50, Punainen Nörtti, Abtract, Jono4174, Satori Son, Thijs!bot, Cekatlow, Nadav1, Smile a While, Escarbot, Jhall1, Gioto, Just Chilling, JAnDbot, Leuko, Bpmullins, DRHagen, Bencherlite, Magioladitis, P64, Martino bridge, EdwardLockhart, Craw-daddy, Mirrorstone, Virginia Dutch, K5s1, MikeLHenderson, Bluejak, DGG, Daredevle, CommonsDelinker, DBlomgren, Trusilver, Ali, Carena sez, Katalaveno, Nemo bis, Boskoman, Eljamin, Mbbradford, Golemarch, Yecril, VolkovBot, Butwhatdoiknow, WOSlinker, TXiKiBoT, Serg!o, Leafyplant, CanOfWorms, Busaccsb, AlleborgoBot, Newbyguesses, Macdonald-ross, SieBot, J0nchan, RJaguar3, Akeyes233, Mam711, Quantumcat, Bede735, Varange2, Mbbn, Spazure, Langus-TxT, Bridge expert, Runner5k, Pinkadelica, ClueBot, The Thing That Should Not Be, EoGuy, Anti.Exams, Brewcrewer, Martinwardle, TheRedPenOfDoom, Hans Adler, CowboySpartan, Lysterbird, XLinkBot, Neilrob, Maudemiller, Dakota Blue Richards, Addbot, RPHv, Severian596, Fieldday-sunday, Kgendler, Jim10701, Schmausschmaus, LinkFA-Bot, Celina030310, Newfraferz87, Ehrenkater, Tide rolls, Lmao kid, Zorrobot, Krenakarore, CComly, Luckas-bot, Yobot, Themfromspace, Ptbotgourou, Keith MapMan, Cyanoa Crylate, Pcap, TomTrottier, Yottamol, ONaNcle, AnomieBOT, Piano non troppo, Tom87020, Materialscientist, Brendankyle, Wispity, LilHelpa, Xqbot, Marvinlf, Eudemis, Sora1995, Viwawanomics, I am ironbatman, FrescoBot, Bridgeblogging, Hobsonlane, Aliotra, Kivgaen, Newwhist, Burkeas, Utility Monster, Crusoe8181, Lotje, Jeffrd10, Wintonian, Ankemeny, Poradevils, EmausBot, John of Reading, Denisegatcurtin, JaeDyWolf, Thecheesykid, Mz7, Werieth, Charlène Bourgeois, ZéroBot, Jsitarz, Hmccasla, Cabegirl09, Anir1uph, Paul Hauff, Kilopi, Orange Suede Sofa, Leewilliams23, Special Cases, Autodidact1, ClueBot NG, LazyJob, Joefromrandb, Chester Markel, Helpful Pixie Bot, Kevlarsen, Zzyxzaa26, John plaut, JZCL, Rjeng2000, Batard0, BattyBot, Victor Yus, Davidjolloyd, ChrisGualtieri, Danb3434, Dexbot, FoCuSandLeArN, Lemnaminor, I am One of Many, Hessmike, Vitani III, Quenhitran, Anshuman1991, Jan Aasen, Cookwald II and Anonymous: 329

13.2 Images

• File:Board,_duplicate_bridge_(1).png Source: http://upload.wikimedia.org/wikipedia/commons/d/d6/Board%2C_duplicate_bridge_ %281%29.png License: CC-BY-SA-3.0 Contributors: Transferred from en.wikipedia; transferred to Commons by User:Maikking using CommonsHelper. Original artist: Original uploader was Radius at en.wikipedia, Created 2005-01-06 by Ray Spalding. • File:Bridge_declarer.jpg Source: http://upload.wikimedia.org/wikipedia/commons/b/b3/Bridge_declarer.jpg License: Public domain Contributors: Originally from en.wikipedia; description page is/was here. Original artist: Original uploader was TerriersFan at en.wikipedia • File:Commons-logo.svg Source: http://upload.wikimedia.org/wikipedia/en/4/4a/Commons-logo.svg License: ? Contributors: ? Original artist: ? • File:Encheres_bridge.jpg Source: http://upload.wikimedia.org/wikipedia/commons/f/f2/Encheres_bridge.jpg License: Public domain Contributors: Own work Original artist: Jastrow • File:Nuvola_apps_kpdf2.png Source: http://upload.wikimedia.org/wikipedia/commons/f/fc/Nuvola_apps_kpdf2.png License: LGPL Contributors: Transferred from en.wikipedia; transferred to Commons by User:IngerAlHaosului using CommonsHelper. Original artist: Original uploader was Equazcion at en.wikipedia • File:Shimer_College_bridge_club_1942.jpg Source: http://upload.wikimedia.org/wikipedia/commons/8/86/Shimer_College_bridge_ club_1942.jpg License: Public domain Contributors: 1942 yearbook of Shimer College Original artist: Shimer College

13.3 Content license

• Creative Commons Attribution-Share Alike 3.0