We have reviewed in a conceptual manner with appropriate scientific detail the role apoptosis plays in diseases of the gastrointestinal tract. This information should help the clinician and clinician investigator to better understand and treat gastrointestinal diseases. Future investigations in apoptosis probably will provide further insight into the cell-signaling cascades regulating apoptosis, the mechanism(s) by which Bcl-2 inhibits apoptosis, and the precise role of apoptosis in cancer initiation, promotion, and progression. We anticipate that in the future, the practicing gastroenterologist will have therapeutic strategies available to inhibit apoptosis for various gastrointestinal diseases associated with cell death and to induce apoptosis for the treatment of gastrointestinal neoplasia.