As a rule, travelers' diarrhea is a self-limited bacterial infection that affects approximately 40 % of travelers to developing countries. Health-care professionals who see returning travelers have noted that some travelers afflicted with diarrhea do not recover completely but, instead, develop chronic diarrhea or a persistent change in gastrointestinal function. Concurrent with this observation has been the recognition that in many patients with long-standing irritable bowel syndrome, an episode of traveler's diarrhea or gastroenteritis preceded the onset of symptoms. Before a diagnosis of postinfectious irritable bowel syndrome is considered, other diagnostic considerations must be excluded. This review will examine an approach to the patient with chronic diarrhea posttravel.