AbstractOne of the most common conditions of low back pain in school- age athletes is spondylolysis. Spondylolysis is a stress fracture of one or both pars interarticularis and most commonly occurs in the lower lumbar spine. Sports such as gymnastic, figure skating, football, throwing sports, volleyball, handball, dancing, diving, butterfly swimming, pole vault and weightlifting etc. place children and adolescents at a higher risk for developing these overuse injuries. (10, 11, 14, 21)Treatment of spondylolysis is a matter of debate. Treatment usually consist of rest and bracing to allow healing to occur, followed by rehabilitation that includes core strengthening.The primary goal of treatment is to achieve a stable pain-free union of the fracture. A bony union is preferred. However a stable, pain free fibrous union that enables full activity has been deemed acceptable by many authors. (14, 18) Diagnostic evaluation typically includes plain radiographs, followed by more sensitive modalities like SPECT, CT or MRI. There is no consensus on the most appropriate protocol for diagnostic evaluation. The purpose of this project task is to tell something about which agreements and controversies which exist in the literature on this field. I will then discuss the results from topics like radiologic investigation, physical treatment, brace treatment and treatment with external electric stimulation of the lesion. Although the athlete has an inherent drive for returning to competition, a safe return to sports should be paramount.