A case-referent study of 345 prostate cancer cases and 1,346 referents was carried out in the Netherlands to investigate the relationship between work environment and prostate cancer risk. Cases were selected from the Cancer Registry of the Comprehensive Cancer Centre IKO. Referents (men diagnosed with benign prostate hyperplasia) were recruited with assistance of the pathology laboratories in the IKO region. Questionnaires were mailed to all subjects to obtain information on their work history and occupational exposure. Moreover, workers in farming (n = 323), and in metal work and maintenance (n = 340), were requested to complete short supplements to the questionnaire inquiring in more detail into specific types of exposure. Significantly elevated risks were found for work in food manufacturing and for bookkeepers. Significantly elevated odds ratios (OR) were also observed for jobs held between 1960 and 1970 in administration, in storage, or as farm laborer. In addition, a statistically significant excess risk was found for subjects who reported frequent occupational exposure to cadmium. Cases who worked in farming applied pesticides during significant more days per year than the referents did. A nonsignificantly elevated OR was found for maintenance of tractors and agricultural machinery. Among metal workers, mechanics, and repairmen, nonsignificantly increased ORs were observed with regard to the use of acids, solvents, iron, and steel, and for welding and maintenance of machinery.