Social rating aims at providing fund managers with objective measures on extra-financial performances. It summarizes the social and environmental companies' profiles and gives a synthetic evaluation. Social rating is often deemed as a transposition of financial rating; as this rating provides financial actors and asset managers who have neither the time nor the expertise to appraise corporate social performances (CSP) with decision-making tools. It could be defined as an independent and objective opinion on environmental and social performances of the organization. Whether financial or social, the rating can be analysed as a "management tool" according to Berry (1983), that is, "material or conceptual means aiming at reducing complexity and at simplifying reality".