Abstract
Based on surveys conducted in 1996 and 2007, this article examines the relationship between trade union influence, as perceived by management, and human resource policy and productivity in Spanish enterprises with over 50 employees. It investigates whether trade unions use their influence to pursue the agenda they have traditionally professed to uphold or whether outcomes differ in practice. The authors identify positive correlations between trade union influence and both wages and absenteeism, but union influence appears to have no effect on the incidence of casual employment, the provision of training, work–life balance policies or information sharing within enterprises.