According to prior reports, blue-collar workers are less likely to participate in worksite health promotion programs than are white-collar workers. This study examined worker participation in the WellWorks worksite cancer prevention intervention, which integrated health promotion and health protection. Analyses were conducted to assess relationships among participation in health promotion and health protection programs, and workers' perceptions of management changes to reduce potential occupational exposures. Results indicate that blue-collar workers were less likely to report participating in health promotion activities than white-collar workers. A significant association was observed between participation in nutrition- and exposure-related activities, suggesting that participation in programs to reduce exposures to occupational hazards might contribute to blue-collar workers' participation in health promotion activities. Furthermore, when workers were aware of changes their employer had made to reduce exposures to occupational hazards, they were more likely to participate in both smoking control and nutrition activities, even when controlling for job category. These findings have clear implications for future worksite cancer prevention efforts.