Well-established indications for supplemental screening breast MRI include: 1) hereditary predisposition that renders a lifetime risk of >20% for developing breast cancer (genetic mutation or pedigree assessment); 2) chest radiation therapy between the ages of 10-30 (when breasts are developing and radiosensitive). Emerging data suggest adjunct MRI screening should be considered for women with LCIS/ALH/ADH and that it may benefit women with a personal history of breast cancer, particularly if initially diagnosed before age 50.