: The existence of peer-to-peer networks is due to benefits brought by decentralisation of control and distribution of resources. It is expected that the usage of such networks will grow and provide support for a variety of applications, including collaborative environments. Since entities participating in those networks are autonomous and therefore free to decide on their level of participation, mechanisms to resolve conflicts between individual and collective rationality are needed. How can implementations of such mechanisms be compared? This paper introduces INCentive frAmework (INCA), a qualitative reference framework, highlighting essential elements and major design decisions in any implementation of incentive mechanisms. In the context of collaborative environments built on top of P2P architectures, the reference framework can be used in assessing the impact on the quality of experience of applications when incentive mechanisms are included.