In 1992, the American College of Radiology (ACR) introduced the Breast Imaging Reporting and Data System (BI-RADS) to bridge the communication gap between radiologists and clinicians. The Breast Imaging Reporting and Data System (BI-RADS) is the result of a collaborative effort among members of the American College of Radiology committees in collaboration with the National Cancer Institute, the Centers for Disease Control and Prevention, the U.S. Food and Drug Administration, the American Medical Association, the College of Surgeons of America, and the College of American Pathologists. The system is designed to provide a quality assurance tool to standardize mammography reporting, reduce confusion in the interpretation of breast images, and facilitate monitoring of results. Through medical review and outcome monitoring, BI-RADS provides important peer review and quality assurance data to improve the quality of patient care. Confusion in the interpretation of breast ultrasound images exists because the terminology of breast lesion characteristics and reporting terminology is not uniform among different investigators in clinical application studies. As early as 1999, Baker et al. suggested that the lack of uniform descriptive terminology could lead to inconsistencies in diagnosis between observers in the evaluation of substantial breast masses. Therefore, in 2003, the ACR updated and introduced the fourth edition of the Breast X-ray Imaging Reporting and Data System (BI-RADS-MMG), along with the first editions of the Breast Ultrasound Imaging Reporting and Data System (BI-RADS-US) and the Breast Magnetic Resonance Imaging Reporting and Data System (BI-RADS-MRI), with the aim of improving the clinical efficacy of breast ultrasound.