The Swedish National Rail Administration, Banverket, has the overarching sector responsibility for Swedish railways, including a responsibility for implementing and managing the government decision for an ecologically sustainable development. In support of achieving ecologically sustainable development and fulfilment of the national environmental objectives and environmental legislation, Banverket initiated the implementation of an Environmental Management System (EMS) in 1998. The overall aim of this thesis is to examine the EMS applied at Banverket with regard to the identification and monitoring of environmental aspects at the administrative Railway Regions of Banverket. The analysis is based on a qualitative approach comprising questionnaires, interviews, document analysis and participating observations