Traveler's diarrhea remains a common health problem among individuals from industrialized nations who travel to developing nations. The syndrome is self-limited and not incapacitating for the majority of sufferers. It affects all age groups with variable frequency and may manifest more severely in the very young. In certain geographic areas, enterotoxigenicEscherichia coliandSalmonellainfections occur more frequently in the summer months whereasCampylobacteris more frequently identified in winter months. When antimicrobial therapy is indicated, the combination of a quinolone and an antimotility agent appears to be safe and effective in decreasing the duration of illness. A nonabsorbable oral monobactam has proven to be safe and effective and may, in the future, be useful in children and in pregnancy. The development of effective oral vaccines, which have proven moderately successful in field trials, offers hope for an alternative modality in the prevention of traveler's diarrhea.