Just as the surgical management of breast cancer has evolved, so too has the field of breast surgery. Patient and surgeon expectations are no longer limited to recreating a breast mound but instead to recreate esthetically pleasing, symmetrical breasts, thus improving quality of life and body image. The number of women undergoing reconstruction continues to increase each year. Breast reconstruction must be accomplished without handicapping any future treatment for the breast cancer and keeping the operation relatively simple, reproducible, and, most important, safe. The surgical changes in the treatment of breast cancer have changed dramatically from the Halsted radical mastectomy to the breast-conserving therapies of today. To perform breast reconstructions or breast reductions, one must know the ideal esthetics of the breasts, the diagnosis, and the surgical reconstructive objectives. This chapter covers breast reconstruction after mastectomies, breast reductions, and oncoplastic breast surgery, an evolving field that combines all available techniques. The surgical description of common reconstructive techniques is described.