The utility of using latest occupational information as a summary of work history is assessed by comparing it to usual occupation and industry. We analyzed 5,734 complete occupational histories obtained by telephone interview as part of an ongoing occupational cancer surveillance study. Of these, 73.6 per cent reported the same usual occupation as latest occupation and 76.6 per cent the same usual industry as latest industry. Differences in match rates by race and sex, occupation and industry titles and categories suggest that bias may result in studies using latest occupation or industry as a summary measure of occupational exposures.