Occupational health services (OHS) are part of the social and health policies of the European Union. OHS has been studied mainly as a national system, as part of a system of occupational health and safety, or as an activity- and process-based service unit for employers and employees. The focus has often been on risk assessment and the prevention of diseases, injuries and accidents. OHS has also gained attention among social partners, such as trade unions and employers' organizations during bargaining and negotiations on compensations for ill health. This study focuses on OHS in the context of the EU and on OHS as part of the work-based benefits provided to workers in welfare states. The study is a policy study on the impact of EU policies, and uses OHS as a case to demonstrate transnational legislation and governance in EU member states. The main reason for choosing the policy process perspective was an obvious need for empirical analysis of OHS in the contexts of the EU, transnational decision-making, and policy environments. The study explores the development of OHS in 15 member states of the European Union at the turn of millennium. The study material included interviews and various types of documents.