Occupational health care has a long tradition in Poland. It has evolved from the industrial health care system established in the post-war period to a modern system defined in the Occupational Health Services Act of 1997. When the process of political and economic transformation began in Poland in 1989, the reforms of the workers' health care became inevitable. The process of introducing and implementing new legal regulations comprised three phases: 1. Introduction of amendments to the Polish Labor Code, according to which employers are now committed to provide their workers with occupational health services (OHS) appropriate to given working conditions. 2. Incorporation into the 1991 Health Care Institutions Act the provisions which allow for the establishment of alternative non-public structures responsible for the health care of the working population. 3. Adoption of the Occupational Health Services Act in 1997, the most important law providing grounds for establishing a most comprehensive system of occupational health services. The Occupational Health Services Act introduces, for the first time, the concept of the OHS system that encompasses the whole working population. The Act outlines a broad range of OHS competences; defines individual tasks; and provides the up-to-date definition of the OHS structure with its two organizational levels, consisting of primary and regional occupational health centers. In addition, the Act specifies the sources of finance for the accomplishment of the defined tasks. Pursuant to the provisions of the Act, OHS units co-operate with employers and employees, bodies supervising working conditions and other organizations involved in occupational health that become their partners in activities aimed at protecting and promoting health of workers. In order to further develop the workers' health care system its constant adaptation to changing conditions is absolutely necessary through: developing modern training for specialists in the field of occupational medicine; establishing an efficient system for controlling the quality of services provided by the occupational health care centers; and implementing more effective forms of health protection and promotion at workplace, especially for those self-employed.