Three atypical colitides (and enterides) are collagenous colitis, lymphocytic colitis, and ileal pouchitis. Collagenous and lymphocytic colitis are similar inflammatory bowel disorders of unknown cause with symptoms including chronic watery diarrhea, occurring in middle age. Pouchitis is the most significant long-term complication in patients with ileoanal pouch anastomosis. The clinical and histologic features and management of these entities are discussed.