Within the MITI CNES/CNRS BOBAFET context, a three days workshop is held in LAM by Laure Ciesla including GECO members (O. Ilbert, V. Buat, R. Gavazzi), IAP and CEA researchers as well as guests from Cambridge. The workshop is dedicated to the modelling of star formation histories of galaxies from multi-wavelength observations and includes discussions with statisticians of the I2M.