A rare condition that can potentially be fatal, immersion pulmonary edema (also known as swimming-induced pulmonary edema, SIPE) occurs when the lungs fill with fluid during a physically exerting swim not associated with aspiration. This case study illustrates the diagnosis and treatment of swimming-induced pulmonary edema in a healthy young male recruit undergoing training at the United States Naval Special Warfare Basic Underwater Demolition/SEAL (BUD/S) course. This case report explores the clinical presentation, pathophysiology, and management of SIPE.