The main question posed in the paper asks why do some cooperative arrangements in agricultural markets survive and succeed and others fail? We define "success" and factors affecting success of cooperation using transaction costs theory and game theory. Transaction costs theory provides insights on comparative advantage of one form of organization versus others and proposes, while game theory focuses on interdependencies between partners entering the arrangements. Data were collected from 62 Polish farmer cooperative organizations called producer groups. The main aim of those organizations was to organize joint sales of output produced individually by their members. Some of the groups were functioning effectively while others that had disbanded or were no longer performing their essential functions. Variables such as the leader's strength, previous business acquaintances, initial selection of members, and number of members have a significant positive impact on the likelihood of success of the researched organizations.