A syndrome of acute pulmonary edema has been previously reported among scuba divers in cold, European waters. Because of the temperatures involved, the name "cold-induced pulmonary edema" was coined in the original 1989 description. We report six individuals who developed the identical syndrome, five while diving in Puget Sound and one in the Gulf of Mexico. The four women and two men ranged in age from 24 to 60 yr. They experienced one to six episodes apiece, each with the development severe dyspnea at depth without excessive exertion. Associated symptoms included cough, weakness, expectoration of froth, chest discomfort, orthopnea, wheezing, hemoptysis, and dizziness. Emergency medical evaluation of four divers revealed rales on examination and pulmonary edema on chest radiograph. In one diver with pulmonary edema on chest radiograph, pulmonary capillary wedge pressure was normal when measured acutely. Symptoms resolved either spontaneously over 1-2 days or with standard medial treatment for pulmonary edema. Prior history of cardiovascular disease was negative except for hypertension and mitral valve prolapse in one diver. Cardiac evaluations following recovery from the acute episodes were normal. Episodes in the cold waters of Puget Sound sometimes occurred despite the use of dry suits. Furthermore, one diver developed recurrent episodes in 27 degrees C water off Cozumel, Mexico. Development of pulmonary edema while scuba diving constitutes a distinct clinical entity which may occur in either "cold" or "warm" water. It is not associated with a decompression mechanism. Personnel caring for divers should be aware of the syndrome in order to provide optimal medical management.