Imaging plays an important role in the diagnosis, staging, treatment and follow-up of breast cancer patients, and can also help predict the molecular subtypes of breast cancers to guide management.Expression profiles have made it possible to define tumors with different prognoses, paving the way for therapeutic strategies tailored to the tumor profile, and even predicting response or otherwise to chemotherapy.The most aggressive breast cancer subtypes are more difficult to diagnose, as their imaging features mimic benign lesions and may therefore be overlooked on standard imaging.Numerous studies have addressed the imaging features of each tumor subtype, and radiologists need to be familiar with them in order to adapt their management.The aim of this book is to explain the molecular classification of breast cancers and the therapeutic strategies adapted to each tumor profile, as well as to illustrate the mammographic and ultrasound aspects of each tumor subtype.