Screening tests in general are meant to reduce deaths from a particular cancer by identifying it early when it is easier to treat and cure. Colon cancer screening has led to a marked reduction in deaths from colon cancer. There are multiple ways to screen for colon cancer, however the mainstays of screening include mainly a colonoscopy in which the entire colon is evaluated from inside with removal and biopsy of any abnormal growths (polyps). Also, stool tests looking for blood as well as DNA changes seen in colon cancer could be used. There are a few other ways to evaluate the colon, such as via CT scan in what is called a “virtual colonoscopy”. However at this point these are options for patients who have either had incomplete colonoscopies, or are not good candidates for colonoscopy or stool testing. The selection of the right screening test for any given patient must take into account any risk factors such as family history of colon cancer or high risk polyps, a personal history of polyps, or any other condition such as inflammatory bowel disease or various familial genetic conditions which increase colon cancer risk. Furthermore, the efficacy of the test for detecting colon cancer as well as detecting larger, higher risk polyps must be factored in. Colonoscopy is one of the best tests for finding cancer and polyps.