MRI of the breast has been established worldwide as a highly accurate imaging modality for breast cancer management in both the symptomatic and screening setting. The Breast Imaging Reporting and Data System (BI-RADS) lexicon contains a structured common language for interpretation and reporting of mammography, ultrasound, and MRI facilitating the communication among physicians through the use of a standardized terminology. The MRI BI-RADS lexicon includes a variety of features from lesion morphology, such as margins, to functional contrast enhancement kinetics. The aim of this talk is to show the basics of the use of BI-RADS on breast MRI.