Colon physiology, the causes of constipation, an approach to management of constipation, and the features of various laxatives are reviewed. The categories of individual agents discussed include the bulk-forming laxatives, stimulant cathartics, saline laxatives, hyperosmotic laxatives, surfactant laxatives, emollient laxatives, enemas and suppositories. Dietary change and attention to proper bowel habits are frequently the only therapy necessary for the treatment of constipation. When laxative intervention is necessary, one of the milder agents should be employed over a short period of time. The chronic abuse of stimulant cathartics, often deeply rooted in family or ethnic traditions, is a significant problem and difficult to treat.