Employees of two large companies in Switzerland took part in a nationwide health information and promotion campaign at work, which included various physical examinations. A total of 5,849 consecutive participants were sent a questionnaire to determine whether changes had been made in their lifestyles and if they had benefited from participation; 2,361 (40.4%) responded. The campaign was rated highly at 8.3 on a scale from 1 to 10. Respondents reported benefiting most from the personal examination results, in particular the measurement of bone density, examination of the carotid arteries and discussions with the staff. Of the respondents, 921 stated they changed their lifestyle in the area of physical activity (64.4%) and nutrition (63.6%). Multiple logistic regression analysis showed the variables predictive of responding were age, hierarchy, diet and smoking. Health promotion at work and the choice of offered examinations may influence the effects of health care promotion at the workplace and the readiness of participants to improve their attitudes to health. Health promotion at work is highly regarded by employees who pay more attention to diet, smoke less and in particular those over 50 yr of age. High-tech equipment in a mobile unit may attract employers and employees may profit most from the individual examination results; 39% of the respondents stated they changed their lifestyle as a consequence of the Check Bus campaign.