In order to find some guidelines for adequate examination of the often very large amount of tissue removed at reduction mammoplasties, a thorough macro- and microscopic study of a total of 400 specimens from 200 consecutive cases of bilateral breast reductions was done. The majority of patients were younger than 30 years of age. In these cases no abnormalities were found and a thorough macroscopic examination performed by an experienced pathologist is believed to be sufficient in this age group. In older women we encountered diverse findings, the most noteworthy being lobular carcinoma in situ in 8% of patients in this series who were over 40 years of age. This indicates the need for generous histological sampling in this age group. The potential value of roentgenological examination is also discussed.