The role of cooperatives in buffering the effects of imperfect markets on smallholder agriculture especially in developing countries has been widely atoned. However, and in spite of eminent advantages, not all smallholder farmers join cooperatives. We use empirical data from coffee farmers in Northwestern Cameroon to identify key factors driving coffee farmers’ decisions to join or not to join a cooperative. Using a standardized questionnaire, data was collected from 140 randomly selected farmers (members and non-members) in contact with North West Cooperative Association Limited (NWCA). Data collection took place in January 2018, with 2017 as the reference period. We use the data to characterize the coffee sector in the region, and to identify key drivers for cooperative membership. 41.4% and 58.6% were NWCA members and nonmembers respectively. The area of land under coffee cultivation, dominant income source, household size, experience in coffee farming, and timely payment of farmers’ dues by the cooperative were the key factors influencing coffee farmers’ decision to join the cooperative or not (P=0.05). Identifying such drivers from farmers’ perspectives and informing policy decisions can increase competitive advantage of smallholder farmers and reduce the effects of market imperfection, as embedded in cooperative concept. This should render the concept once more attractive and portray it as a rational option to many smallholder farmers.