Over the past 5 years there has been a marked increase in the use of magnetic resonance imaging (MRI) of the breast. Multiple research studies have confirmed improved cancer detection, diagnosis, and evaluation of response to therapy with breast MRI compared with mammography and ultrasound. As this exciting new technology advances, focused work in optimal scan protocols, appropriate clinical applications, and image interpretation are needed. Both the potential benefits and harms need to be evaluated to guide optimal use of this imaging modality in select patient populations.