In Germany approximately 29,000 people died of colorectal carcinoma (CRC) in 2002; the risk of getting CRC is 4-6% in Germany, rising with age from the 50th year of life. About one third of all people over 50 years of age have polyps with the potential for malignant transformation in the colorectum, which is a sufficiently high prevalence rate to justify screening. In contrast to most other cancer diseases, in the case of CRC it is possible to prevent the cancer and not only to detect it at an early stage. Application of the test for occult blood in persons between their 45th and 80th years can reduce the mortality of CRC by 14%. We can assume that already regular sigmoidoscopies with consistent performance of polypectomy when needed could reduce the incidence of CRC by 50-70%. There is no doubt that coloscopy is the technique of choice for secondary prevention, as it unites the possibility of complete diagnosis and treatment with a justifiably low level of risk. The economic advantages of an avoidance strategy compared with the treatment of CRC, which is certainly expensive, have been documented. On the basis of all the data reported, in the case of CRC preventive strategies can be emphatically recommended.