Underwater diving may cause several unique neurologic injuries because of exposure to rapid changes in pressure and volume. DCS, which results from extended deep dives and too rapid ascent, is a systemic disease that frequently causes spinal cord injury but may involve other organs as well. AGE results from pulmonary overpressure on ascent, with extravasation of air into the arterial system, and causes stroke-like brain injury. Both conditions are of sudden onset, progress rapidly, and require urgent attention. Definitive treatment includes administration of oxygen and recompression in a chamber. Permanent neurologic injury may result.