This study focuses on the prediction of the engagement of small and medium sized enterprises (SMEs) in environmental management practices, based on a random sample of 689 SMEs. The study finds that several endogenous factors, including tangibility of sector, firm size, innovative orientation, family influence and perceived financial benefits from energy conservation, predict an SME’s level of engagement in selected environmental management practices. For family influence, this effect is found only in interaction with the number of owners. In addition to empirical research on SMEs’ environmental behavior, the article draws on the ecological modernization literature as well as the theory of planned behavior.