Colorectal is a major health problem in industrialized countries. Cancer registries have reported relatively large variations in incidence throughout the world. The incidence has been increasing over time. Colorectal cancer fulfills the conditions required by mass screening. Data from randomized studies indicate that it is possible to reduce colorectal cancer mortality in people who accept screening with faecal occult blood test. Time has come to implement well-organised population-based faecal occult blood screening in subjects aged between 50 and 74 despite current limitations of available tests.