Recent evidence from prospective cohort studies suggests that women at high risk for breast cancer based on their family history or genetic testing, including BRCA1/2 mutation carriers, benefit from screening that includes magnetic resonance imaging (MRI) in addition to mammography (Kriege et al., 2006; Kuhl et al., 2005, 2010; Leach et al., 2005; Lehman et al., 2005; Sardanelli et al., 2011; Warner et al., 2004, 2011). This evidence concerns the gene BRCA1 and breast cancer.