In the end of the1940's Occupational Medicine was institutionalised in Sweden. Health hazilards in the work place was not a new field for the Swedish physicians. They had been preocrcupied with these problems for a long time. The aim of this thesis is to analyse and describe how health hazards in the work placees, ecpecially in the factories, were perceived and described by Swedish physicians at the turn of the 20t century. The aim is also to clarify the physicians' role m shaping, developing and supervising the Occupational Safety and Health Acts. The city of Norrköping is used as anexample in discussing how physicians at a local level paid attention to health and safety issues in the work place. According to the physicians, there were a number of harmful factors in the factory work that could endanger health, but these were also seen to be dependent on the worker. Workers ldisplayed different kinds of vulnerability to the harmful factors. Sex, heredity, age, health, physique, habits and behaviour were understood as determining components. The preventive measures not only contained guidelines for the factories. They also included advises on how '!the workers should organise and live their lives outside work. The life style and behaviour the physicians would like to encourage were aligned with the !cultural values of the bourgeoisie at the tum of the 20th century. It is vital to recognise the cultural lens through which the physicians perceived and spoke of the workers' situation, their way of life and their behaviour inside as well as outside the factory.