During breast augmentation, one has to differentiate between aesthetic breast enlargement (possibly in combination with a breast lift or as part of breast asymmetry), therapy for capsular fibrosis, micromastia in connection with a tuberous or tubular breast, and breast reconstruction after cancer therapy after ablation/mastectomy, radiation therapy, or breast retention therapy. A special case is represented by the more frequently occurring subcutaneous mastectomy in case of DCIS (ductal carcinoma in situ) as well as breast cancer gene (BRCA 1, etc.). Preoperative expanders are frequently used in reconstructive cases for expanding the tissue before lipofilling. This article also discusses pectus excavatum (sunken chest) and the Poland syndrome.