In this paper we aim to investigate the underlying mechanisms of the maintenance of ISO 14001. Initially, we looked into the Hillary’s [Hillary
R. Evaluation of study reports on the barriers, opportunities and drivers for small and medium sized enterprises e the adoption of environmental
management systems. Report for DTI Envirodoctorate 5th October, 1999. London: NEMA; 1999] evaluation study on barriers,
opportunities and drivers for small and medium enterprises that adopted environmental management systems and we developed a comprehensive
list of barriers identified in the literature.