Overall, whitewater sports are relatively free of serious medical problems, with submersion accidents, trauma, and overuse syndromes being the most commonly encountered afflictions. Various infectious diseases and environmental exposure problems may occur, but serious illness or injury from such causes is infrequent. Nonetheless, the growing popularity of whitewater sports, along with increasing attempts by less experienced persons to navigate more difficult rivers, underscores the need for physicians to be aware of the medical problems likely to be encountered in these activities so that they may appropriately counsel and prepare persons for these invigorating yet potentially dangerous pastimes.