Early diagnosis and treatment of septic arthritis improves the potential for a favorable outcome. The accepted treatment for acute septic arthritis involves drainage of the pus, a systematic antibiotic treatment program and a stable joint. Septic arthritis is diagnosed with a white blood cell count of more than 50000 per mm3 in synovial fluid. Monitorization of the treatment response should be performed using sedimentation rate and C-reactive protein level. The culture-negative septic arthritis is more common than the other culture-negative forms of musculoskeletal infection. The same aggressive treatment is recommended in those cases with and without identification of a causative organism. Repeated aspirations of superficial joints such as ankle and knee should be performed to treat the symptoms. As the infection resolves, joint movement is started, including functional splinting initially to prevent deformity and isometric muscle strengthening, and active range of motion exercises to prevent functional impairments. Septic arthritis of the hip is very common in children, and may result in severe disability. Clinical problems include pain, instability, abductor insufficiency, and leg length discrepancy. The treatment must be individualized, and many treatment options are available.