This article summarizes ACOEM's evidence-based diagnostic guidelines for low back disorders. Recommendations are given for these diagnostic tests: functional capacity evaluations, roentgenograms (x-rays), magnetic resonance imaging (MRI), computerized tomography, myelography, bone scans, single proton emission computed tomography, electromyography, surface electromyography, ultrasound, thermography, fluoroscopy, videofluoroscopy, lumbar discography, MRI discography, and myeloscopy. Diagnostic testing is not indicated for the majority of patients with low back pain.