Low back pain is a common reason for patient visits to a health care provider. For most patients, low back symptoms are nonspecific, meaning that the pain is localized to the back or buttocks and is due to a presumed musculoligamentous process. For patients with radicular leg symptoms, a precise etiology is more commonly identified. The history and physical examination usually provide clues to the uncommon but potentially serious causes of low back pain, as well as to those patients at risk for prolonged recovery. Diagnostic testing should not be a routine part of the initial evaluation, but used selectively based upon the history, examination, and initial treatment response. For patients without significant neurological impairment, initial treatments should include activity modification, nonnarcotic analgesics, and education. For patients whose symptoms are not improving over 2 to 4 weeks, referral for physical treatments is appropriate. A variety of therapeutic options of limited or unproven benefit are available for patients with radicular leg symptoms or chronic low back pain. Patients with radicular pain and little or no neurological findings should receive conservative treatment, but elective surgery is appropriate for those with nerve root compression who are unresponsive to conservative therapy.