This study investigates the consistency of occupational histories reported by the same men in 1985 and again in 1988. Detroit-area pattern and model makers participating in a colorectal cancer screening program that was offered at 3-year intervals completed a career length occupational exposure questionnaire at each screening. Analysis of the data from the 243 men who participated in both screening programs provided the opportunity to examine the consistency with which these workers reported the extent of their exposure to 13 substances commonly found in their work environment. Workers were asked to provide a work history, and for each different pattern or model maker job they had held, to estimate the percentage of time they were exposed to the 13 substances. The data indicated that over the 3-year study period, pattern and model makers were highly consistent in reporting whether or not they were exposed to the 13 substances. In addition, their first estimates of the percentage of time they were exposed to each substance were within 10% of their second estimates more than 70% of the time. This concordance was somewhat diminished after excluding those who reported no exposure. These findings suggest that skilled tradesman can provide occupational exposure information that is likely to be useful for physicians in considering an occupational cause for a presenting health concern.