During the last twenty years, the evolution of public policies in Southern countries has been characterized by the implementation of liberalization processes, which can be analyzed through Douglass North's institutional change approach. In Costa Rica, liberalization processes, that mainly consisted in State withdrawal and frontiers' opening, led to private actors' empowering and induced different strategic behaviors among rural producers' organizations. In this paper, we carry out a comparative study of four farm sectors (coffee, milk, black bean and pineapple), based on a dynamic approach of behaviors in relation with institutional changes occuring during the liberalization process. We highlight organizations'capacities to adapt and participate to institutional changes by (i) implementing economical activities and (ii) acting upon public policies. We underline the fact that rural producers organizations play a key role in farm sectors' efficiency and sustainability, permiting both producers' market insertion (acces to domestic and world markets) and political participation (obtention of public suppports). We show that the conditions for success of collective action depend on organization's mental models and organization's resources endowment, and are in line with pathdependent logic. More generally, our study allows us to get a better understanding of institutional and economic dynamics.