Colorectal cancer (CRC) is the second most frequent malignant growth in developed countries. Secondary prevention of CRC includes two types of programs: 1. Screening of asymptomatic subjects starting at age 50. 2. Surveillance of high risk groups. The guaiac occult blood test is used for CRC screening most widely. Other options include: flexible sigmoidoscopy, a combination of both tests, colonoscopy and virtual colonography. Surveillance programs are tailored to the extent of risk in individual groups. At present effective guidelines are available, which may reduce CRC morbidity and mortality both in average and high risk groups.

        Key words: colorectal cancer, secondary prevention, screening, surveillance