Determinants of trade union membership

A large number of potential determinants of union membership, which often can be interpreted in terms of costs and benefits, have been incorporated into economists' traditional supply and demand framework or into new models of an individual's decision to unionise (such as social custom theory). A review of the international empirical evidence shows that business cycle factors and structural developments are important macro-determinants, whereas micro-determinants include personal, occupational and firm characteristics, earnings, attitudes and social variables. In addition, institutional determinants such as a union-affiliated unemployment insurance play a role. What is often missing, however, are attempts to integrate macro- and micro-level findings and cyclical, structural and institutional explanations of unionisation.