This review targets the current role of the pathologist in the diagnosis and management of breast disease, a responsibility that evolved along with an increasingly complex approach to human breast cancer. We will focus on the three major areas of this responsibility: premalignancy, highlighting the atypical hyperplasias; the carcinomas in situ, highlighting low grade ductal carcinoma in situ; and the stratification and prognosis of invasive carcinomas. It will be evident that with the advent of an increasingly rich menu of treatment options, the challenge to identify an optimal categorization of breast cancer and its putative precursors is not static.