Colon cancer is the most common form of cancer in Germany. Early detection of colon cancer can increase the recovery rate to more than 90% of patients. In cooperation with the University of Frankfurt (First Medical Clinic) the Lufthansa Medical Center started a broad screening campaign aimed to get as many employees as possible to take part in a secondary prevention program. After promotion of the campaign in company media, 3223 employees reported interest and from these 2206 stool-samples were evaluated. The test methods Fecal-Occult-Blood-Test (Haemoccult, Beckmann Coulter GmbH) and the immunological test (Prevent ID CC, Preventis GmbH) were used once on every sample. On the basis of the results, coloscopy was recommended to 204 of the tested persons; of these 59.31% are known to have had the coloscopic examination. In these coloscopies, 25.62% of persons were found to have polyps and one a manifest carcinoma. For the precancerous lesions, analysis for the age group 51—60 years revealed a cost-benefit factor of +8.6.