Colon cleansing preparations for diagnostic and surgical procedures continue to be evaluated in an effort to improve the quality of colon exam. Modifications of older barium enema x-ray preparations have led to the development of many alternative forms of bowel cleansing. Formal study has allowed carefui comparison of gut lavage, diet and cathartic as well as oral sodium phosphate preparation. Gut lavage with electrolyte lavage solutions represents the most popular form of bowel preparation. Patient variability and special circumstances such as gastroparesis, surgically altered anatomy or patient preferences may dictate selection of colon cleansing preparations.