Abstract: Cooperation is one of the characteristics of a multi agent system In this paper abstract cooperation models of multi agent system with requirement/service interaction property are examined According to the service request forces and service offer manners, six fundamental abstract cooperation models and corresponding atomic communication acts are put forward The rigorous semantics of the communication acts and the cooperation models are formally defined, and the corresponding implementation mechanisms are further analysed The work can be used to specify the different cooperation manners in a multi agent system, and facilitate its analysis and design