Abstract The effects of organizational factors on participation rates in a smoking cessation clinic and on one-year quit rates were examined among 68 private sector businesses. Free smoking cessation programs were offered to all smoking employees. Smokers (n = 844) were contacted to determine changes in smoking behavior; managers (n = 68) were also contacted to assess changes in smoking policy implementation over the past year. The participation rate in the clinic was 6.6 percent. Overall, 14.3 percent of smokers reported abstaining from cigarettes for at least one month prior to the one-year follow-up survey. Organization factors predicting clinic participation included having health promotion programs, increased motivation to stop smoking, and greater length of employment. Factors predicting cessation at one year included greater clinic participation rates, larger worksite size, a greater awareness of smoking restrictions, and agreement that passive smoking was dangerous to ones health. The only factor to significantly increase both participation and cessation rates was the presence of smoking policies. Employee, manager, and organizational characteristics can exert independent effects on behavior. Therefore, interventions should be targeted at each of these levels to maximize smoking-related behavior change.