The interdisciplinary team (business and accounting, computer science, economics, econometrics and sociology) intends to describe the causes and consequences of downsizing and to assess its causal effect upon the performances of companies, at the firm and group levels, in contemporary France (1996-2015). The team uses the econometric methods developed for evaluation studies, notably the differences-in-differences model using propensity-score matching. Then, the team focuses on the impact of sales shocks on employment changes. The team also assesses the survival bias that depends on the probability for a company to go bankrupt. The team combines sources that are hardly matched (LIFI, DADS, DMMO, BRN, FARE, FICUS and BODACC) and develops an original database. It relates these information for stand-alone companies and it enriches these sources for subsidiaries with the consolidated annual accounts of the groups that are listed in the CAC All-Tradable and the downsizing operations that have occured withhin their perimeters.