This report presents the findings of a case-control study of lung cancer among workers at a rubber manufacturing plant. Detailed work histories of 40 lung cancer deaths, which occurred during 1977 and 1978, were compared with those of 146 controls who were individually matched to cases on age, sex, and race; 66 of the controls were also matched on year of first hire. Elevated odds ratios were noted for different durations of employment in four work areas: Reclaim Operation, Chemicals, Special Products Manufacture, and Curing Preparation. A clear trend of increasing odds ratios with increasing durations of exposure was observed for the first three of these work areas. Several chemicals used in these processes are known respiratory system hazards. The results of this study suggest an association between lung cancer mortality risk and employment in Reclaim Operation, Chemicals, and Special Products Manufacture. A moderate excess risk was observed in these areas among both smokers and nonsmokers, although the risk was greater among the smokers.