The fertility status of male employees engaged in the production of chlorinated three-carbon compounds at Dow Chemical Company's Texas Division was investigated. Males who had not worked in the production of industrial chemicals for at least five years prior to the study period served as controls. Data were obtained from a reproductive medical history, from hormone determinations, from a physician's examination, and from a semen analysis. Sperm counts and percent normal sperm forms were major study variables. Comparisons were made between the control and the study groups and within the study group only for duration of exposure, strength of exposure and a combination of the two. Specific chemical exposure subgroups within the study group were also compared. Although the participation rate for the exposed group was relatively low (64%), results indicated no detrimental effect on fertility from exposure to chlorinated three-carbon compounds at levels occurring in the specified work environment.