The commitment of members reduces as an agricultural cooperative grows larger. Using a multinomial logit model, we explore how the alignment of members’ objectives and those of cooperatives influence member commitment. Our study is based on a sample of 3,205 members of a French multipurpose cooperative. We show that the availability of outlets and supplies to members strengthens it. Furthermore, the adoption of new agricultural practices has a small but significant effect. Other determinants, such as farm organization, or geographical distance to the cooperative headquarters reinforce member commitment.