Endometriosis. An important condition in clinical gastroenterology. Endometriosis, a condition defined by the presence of ectopic endometrium, is a disorder of increasing incidence and a significant cause of gastroenterologic distress in young women. Although clinical manifestations vary considerably depending upon the anatomic extent of disease, characteristic abdominal complaints and typical physical findings continue to be associated with misdiagnosis and delayed recognition of gastrointestinal involvement. The authors of this paper review the medical literature concerning endometriosis of the digestive tract--emphasizing modes of presentation, risk factors, diagnostic testing, complications, and therapy. Greater familiarity with the disease and heightened awareness of its sequellae are needed and prerequisite to improved medical management. 