Background: Physical inactivity and obesity are major public health problems. Our objective was to investigate the effectiveness of an individual counseling intervention at the workplace on physical activity fitness and health. Counseling content derived from the Patient-centered Assessment and Counseling for Exercise and Nutrition (PACE) program. Methods: A total of 299 employees of three municipal services in the Dutch town of Enschede were randomly allocated into intervention (n =131) and control group (n =168). Over a 9-month period, intervention group subjects were offered seven counseling sessions. Counseling was based on the individual's stage of behavioral change using PACE physical activity and nutrition protocols. Subjects in both the intervention and control group received written information about several lifestyle factors. Primary outcome measures were physical activity (total energy expenditure, during sports activities, during physical activity leisure time other than sports, and meeting the moderate-intensity public health recommendations); cardiorespiratory fitness; and prevalence of musculoskeletal symptoms. Secondary outcome measures were body composition (body mass index [BMI], and percentage of body fat measured via skinfold thicknesses); blood pressure; and blood cholesterol. Results: There were significant positive effects on total energy expenditure, physical activity during sports, cardiorespiratory fitness, percentage of body fat, and blood cholesterol. No effects were found for the proportion of subjects meeting the public health recommendation of moderate-intensity physical activity, physical activity during leisure time other than sports, prevalence of musculoskeletal symptoms, body mass index, and blood pressure. Conclusions: Individual face-to-face counseling at the workplace based on PACE protocols positively influenced physical activity levels and some components of physical fitness. The implementation of workplace counseling programs for individuals should therefore be promoted. © 2003 American Journal of Preventive Medicine.