Image credit: Giovanni Tentori Giovanni credit: Image Astrophysical Polarimetry in the Time-Domain Era September 1-4 2020 Politecnico di Milano Polo territoriale di Lecco Via Previati 1/c – 23900 Lecco, Italy Modern astrophysics is increasingly characterized by large surveys able to identify transient or highly variable sources belonging to many different categories: supernovae, gamma-ray bursts, x-ray binaries, gravitational wave counterparts, flaring stars, novae, tidal distruction events, blazar outbursts, and numerous transients of unknown nature. Transient sources or phenomena represent unique SOC laboratories of unusual or even extreme physical Stefano Covino (INAF-Osservatorio Astronomico di Brera) - chair conditions, often linking together multi-messenger Paolo D’Avanzo (INAF-Osservatorio Astronomico di Brera) observations. Among the many possible analysis tools, Andreja Gomboc (University of Nova Gorica · Center for Astrophysics and Cosmology) Diego Götz (Service d’Astrophysique, CEA/DSM/Irfu, Saclay) (time-resolved) polarimetry offers the possibility to Jennifer Hoffman (University of Denver) derive information about geometry, including magnetic Elina Lindfors (Finnish Centre for astronomy with ESO, University of Turku) Justyn Maund (Department of Physics and Astronomy, University of Sheffield) field orientation, and physical processes driving the Carole Mundell (Department of Physics, University of Bath) evolution of these events not easily obtainable by Pierre-Olivier Petrucci (Institut de Planétologie et d’Astrophysique de Grenoble) Nando Patat (European Southern Observatory) other techniques. New observatories have opened up Elena Rossi (Leiden Observatory) an unprecedented wavelength range for polarimetry, Paolo Soffitta (INAF-Istituto di Astrofisica e Planetologia Spaziali) Kenji Toma (Tohoku University) from radio to gamma-ray, providing new views on Klaas Wiersema (University of Warwick) astrophysics, and establishing polarimetry as a key capability to exploit the yield of large scale transient LOC surveys. Paolo D’Avanzo (INAF-Osservatorio Astronomico di Brera) - chair Stefania Aldeghi (UniverLecco) Maria Grazia Bernardini (INAF-Osservatorio Astronomico di Brera) This workshop aims at joining together theoreticians, Andrea Melandri (INAF-Osservatorio Astronomico di Brera) observers, and instrument scientists to establish a Arianna Miraval Zanon (INAF-Osservatorio Astronomico di Brera) profitable interaction based upon polarimetric studies..