This publication provides evidence-based evaluations of the effectiveness of colorectal cancer screening in reducing colorectal cancer incidence and mortality. The Working Group also reviewed the body of evidence on the comparison of endoscopic and stool-based techniques, on the determinants of participation in screening programs, and on the most mature emerging techniques that may be alternatives to current practices for colorectal cancer screening, as well as presenting the different categories of high-risk populations and the surveillance strategies for such individuals.