Decentralization and people's participation have been key features of government environmental policy since the 1990s. In Madagascar, the policy of Secured Local Management of Natural Resources, known as the GELOSE act, has created a framework for the transfer of rights from central government to local communities. This article analyses the practical implementation of this policy by focusing on the nature of the rights transferred and on the nature of the contracts and incentives developed. The Aghion and Tirole model for allocation of formal and real authority in an organization is used to shed light on the contractual definition process and on the trade-offs between giving responsibilities to local communities and losing control over natural resources management. It is shown that a congruence of interests between the parties is crucial for effective delegation of authority to local communities and that this congruence may emerge in relation to the transfer of exclusion rights.