This article analyses the EEC development policy between 1957, year of the signature of the Rome’s Treaties, and 1975, signature of the Lomé Convention. In the first part, we examine the origins of the development policy, also called “Association policy” because the African colonies were associated to the EEC. In the second part, we analyse the two Yaoundé Conventions of Association (1963 and 1969) signed by the European and the African states. During this period the Six concentrated their discussions on the reform of the Convention after the independence of the African countries and the creation of UNCTAD. In the last part, the article focuses on the Seventies and on the Lomé Convention which renewed the instruments of the European Development policy and the relationship between the Nine and the Developing states. The negotiations of the three Conventions (Yaoundé I, Yaoundé II and Lomé) represent good opportunities to study the motivations and the role of the most important actors. Also, the evolution of the European development policy is analysed in relation with the changes of the international context.