Piriformis syndrome is an often misdiagnosed cause of sciatica, leg, or buttock pain, and disability. The sciatic nerve may be compressed within the buttock by the piriformis muscle, with pain increased by muscular contraction, palpation, or prolonged sitting. A thorough medical history and physical examination are essential to proper diagnosis. Diagnostic testing may be used to differentiate piriformis syndrome from other causes of sciatica, lower extremity weakness, and pain. This article reviews the pathophysiology and management of piriformis syndrome.