This text is designed to present a practical and concise handbook on the diagnosis and management of breast diseases for quick reference by trainees and practitioners. It emphasizes the approach to diagnosis and management of breast tumors written from the perspectives of each member of the multidisciplinary management team (pathologist, radiologist, medical oncologist, surgical oncologist and radiation oncologist). The text is divided into two sections. The first section is written by each subspecialty with focus on the overview and management of breast tumors, current controversies, position statement when necessary, and quality assurance.