Expensive advanced imaging, such as magnetic resonance (MR) imaging, contributes to the unsustainable growth of health care costs in the United States. Evidence-based imaging decreases costs and improves outcomes by guiding appropriate utilization of imaging. Low back pain is an important case illustration. Despite strong evidence that early advanced imaging with MR imaging for uncomplicated low back pain leads to increased costs without significant clinical benefit, MR imaging utilization for acute low back pain has increased. Barriers to evidence-based imaging can be traced to patient- and physician-related factors. Radiologists have a critical role in addressing some of these barriers.