Abstract : To demonstrate and quantify the forage and environmental services provided by permanent grasslands, a research program (2008-2011) was performed, including together INRA, Institut of Elevage and 23 extension services. A national network of 190 permanent grasslands was sampled in a database of 1500 grasslands, to represent the diversity of management and agroclimatic conditions, and has been studied for two years. On each plot, a botanical survey was carried out (2009). Grass production, functional composition of the grassland and forage nutritive value for ruminants were measured at four dates during the growing season (2009, 2010). Data of functional and botanical composition were analyzed to define 19 types of grasslands identifiable from a simple decision key (agro-climatic conditions, management). For each type, quantitative references of seasonal evolution of functional composition, biomass production and nutritive value are provided. The contribution of the different types of grasslands to ecosystemic services was evaluated.