In many cases, breast deformity caused by partial mastectomy can be reduced or corrected by plastic surgery. Partial breast reconstruction is best performed immediately after the partial mastectomy using an approach determined by the size of the breast and the defect. Small defects in large breasts usually need no reconstruction. For larger defects in large breasts, breast reshaping (similar to reduction mammaplasty) combined with a contralateral breast reduction is usually the best option. For medium-sized or smaller breasts with small to moderate-sized defects, local flaps from the subaxillary region are very useful. If the defect is too large for correction with local tissue, a latissimus dorsi myocutaneous flap is usually the best choice. Using these techniques, patients can achieve aesthetically better outcomes from breast-conservation therapy, even when larger tumors are being treated or when wider margins are taken to reduce the risk of tumor recurrence. By working together with an oncologic surgeon and facilitating the removal of larger tumors, the plastic surgeon can widen the indications for both breast-conservation therapy and breast reconstruction at the same time.