Few studies have reported on the implementation and the development of a contract as a learning process of the actors. Individual farmers of São Tomé had to organise themselves to respect a manufacturer's demand for a new organic and fair cocoa contract. Such a relational construction between actors of a contract is a base, a guarantee of its sustainability. How should this have happened? Our aim is to contribute to the understanding the setting up of such a collective cocoa contract as a means to achieving autonomy; that is to say the answer to the question of emancipation. We analysed how the relationship between the manufacturer and the farmers evolved, what was their technical and organisational impact, and which perspectives about the sustainability of the relationship.