The agri-environment measure 'Flowering meadows' aims to preserve the biodiversity of permanent grasslands. The measure is based on a list of specific plants that have to be maintained. It is an innovative measure in that it is performance-indexed to ecological results, while farmers are left free to decide how to implement the measure. We aimed to identify and understand farmers' practices on contract-scheme grasslands, the roles these grasslands play in the forage system, and the reasons that prompted the farmers to sign the contract. We surveyed 21 farmers in two Regional Natural Parks in French mountain areas. Farmers establish a relationship between on-grassland biodiversity and organic manure management. The role of contract-scheme grasslands in the forage system varies greatly due to different farmers' strategies. Subsidies were a motivation, but the main driver is that farmers see the contract as a social recognition of their practices and skills.