Recent work has shown that polyethylene glycol-electrolyte lavage solutions provide adequate cleansing in preparation for colonoscopy, barium enema, intravenous pyelography, and colon surgery. It is safe and well tolerated by patients, and seems ideal for those with renal or cardiovascular disease who must undergo colon cleansing. We review the development of polyethylene glycol-electrolyte lavage solution and the clinical experience with various colon-cleansing preparations.