Colon cancer is the third leading cause of cancer among men and women in the United States. Colonoscopy is largely used as a screening tool to detect pre-cancerous polyps and to detect colorectal cancers early. Optimal bowel preparation prior to colonoscopy allows the endoscopist the ability to increase adenoma detection rates and perform the procedure more safely. This article reviews the various bowel preparations on the market today with evidence based findings on optimal use, safety profiles, timing and adjuncts.