Reciprocity is a powerful determinant of human behaviour in social exchange situations where mutual reinforcement exists between two parties. Consequently, it is supposed to be one of the fundamental resources of cooperatives. Mandatory Cooperatives is a special category of cooperatives that is characterized by a higher degree of reciprocal behaviour among members than traditional cooperatives. This paper examines the differences in financial level of these two categories (mandatory cooperatives versus traditional agricultural cooperatives) with the help of a financial approach, which is based on panel data analysis techniques. Several notions and concepts forming the financial engineering methodological framework are adopted for the design of this approach. The results reveal that reciprocity is a very important element that leads cooperatives to higher performance levels.