A cohort study was conducted of the membership of a large international union of painters and allied tradesmen. The union membership consisted of both painters and associated trades such as glaziers and tile and carpet layers. The study examined the mortality experience of 57 175 current and former union members in four states (California, Missouri, New York, and Texas) in the United States (US) from 1975 through 1979. No excess mortality was observed for the total union membership when compared to that of all US white males. When the study population was subdivided by the trade affiliation, members of locals comprised primarily of painters exhibited a significant elevation in mortality from all malignant neoplasms, lung cancer, and stomach cancer, compared to all US white males. To reduce the impact of potential nonoccupational differences between the study population and all US white males, the data were also analyzed using the entire cohort as the standardization population. Significant elevations continued to be observed for all malignant neoplasms and lung cancer among the membership of painting locals compared to other locals. In addition there was a statistically significant difference in mortality from leukemia and cancer of the bladder observed between the groups.