Screening for colorectal cancer is almost uniformly recommended for average-risk asymptomatic persons aged 50 years and older and it may substantially reduce its relative mortality. However, consensus is lacking about the type of screening test. Flexible sigmoidoscopy followed by colonoscopy in the presence of adenoma(s), detect 70% of the neoplasms and should be recommended for adults aged 50 years and older. Colonoscopy with polypectomy may ultimately become the preferred strategy after 60 years and certainly in the presence of alarm signs and personal or familial risks for colorectal cancer.