The focus of the study is the identification of the economic position and perspectives of suppliers of environmental technology and services, the structures of co-operation as well as the technological possibilities in Berlin. The methods utilised include a postal questionnaire, as well as interviews with firms and experts in this field. It can be summarised that the performance of this branch in Berlin is rather good even compared to average national performance. Another main part of the study was to identify the behaviour of firms concerning sustainable development. One result of the survey was that, in comparison to firms in Germany as a whole, sustainable development was not a central topic for the top management of Berlin based firms.