A standard tool for the analysis of known and suspected causes of occupational lung cancer in population-based studies is proposed in order to allow comparable definitions of exposure or of categorizations of occupations. It is based on a list of occupations and industries known (list A) or suspected (list B) to be associated with lung cancer. The lists were translated into codes of the International Standard Classification of Occupations (1968) and the International Standard Industrial Classification (1971). The specificity of the categorization is compromised for some groups that are defined by highly specific production processes or exposures. Nevertheless, the grouping is based on a highly valid source of information in population-based studies. It is proposed for use in the assessment of the public health impact of occupational lung cancer.