Numerous civilian and military personnel are involved in SCUBA diving activities. In this day of rapid air travel it is important that all physicians, not just those living near the coast or dive centers, be familiar with the basics of diagnosing and treating diving-related injuries. One of the more serious complications of dysbarism is Arterial Gas Embolism (AGE). This case history involves an atypical presentation of delayed onset AGE in a military diver trainee, and its treatment. This article then reviews the incidence, etiology, pathophysiology, ''classic'' presentation and current treatment of this disease. Systemic pathophysiology secondary to the effects of intravascular air of AGE is also discussed.