Decompression illness (DCI) occurs due to absorbed extracorporal gas resulting from a decrease in environmental pressure during decompression. This term includes both arterial gas embolism (AGE), where alveolar or venous gas emboli enter the arterial circulation, and decompression sickness (DCS), which may result from in-situ bubble formation due to dissolved inert gas. AGE commonly presents with stroke-like symptoms affecting the brain, while DCS can impact various organs including the brain, spinal cord, inner ear, musculoskeletal tissue, cardiopulmonary system, and skin. DCI symptoms vary widely in nature and severity, ranging from itching and minor pain to severe neurological symptoms, cardiac collapse, and death. Symptoms are mostly non-specific; therefore, the diagnosis of DCI is based on careful evaluation of the circumstances of the dive, known risk factors, and the post-dive latency and nature of the manifestations. Treatment of choice is the on-site administration of 100% oxygen as soon as possible after onset of symptoms. First aid also includes supportive general care, immobilizing the injured patient, and giving isotonic fluids. Adjunct pharmacotherapy is usually not recommended; NSAIDs (Non steroidal anti-inflammatory drugs) can be used if there are no contraindications. Hyperbaric oxygen therapy is the primary treatment for decompression illness due to its ability to reduce bubble volume, enhance tissue oxygenation, and ameliorate inflammatory responses that contribute to tissue injury. Most DCS cases respond well to a single hyperbaric session, but repetitive treatments may be needed based on initial response. Delayed intervention is associated with increased morbidity and residual sequelae. Adhering to conservative dive profiles and screening for medical risk factors can reduce risk of decompression illness. This clinical review summarizes current knowledge on the pathophysiology, clinical presentation, diagnostic approach, treatment, and prevention of dive-related DCI. Key Words: Arterial Gas Embolism, AGE, DCS, Diving, Treatment, Pathophysiology, Diagnostic, Prevention