Although preservation of the sensitivity of the nipple and areola is an important goal in breast surgery, only scant and contradictory information about the course and distribution of the supplying nerves is found in the literature. The existing controversy might be due to the difficulty in dissecting the thin nerves and to frequent anatomic variations that bias the results if only a small number of cadavers are dissected. We dissected 28 female cadavers and found that the nipple and areola were always innervated by the lateral and anterior cutaneous branches of the 3rd, 4th, and 5th intercostal nerves. The most constant innervation pattern was by the 4th lateral cutaneous branch (79 percent) and by the 3rd and 4th anterior cutaneous branches (57 percent). The anterior cutaneous branches took a superficial course within the subcutaneous tissue and terminated at the medial areolar border in all dissected breasts. The lateral cutaneous branches took a deep course within the pectoral fascia and reached the nipple from its posterior surface in 93 percent of the dissected breasts. In 7 percent of the dissected breasts, the lateral cutaneous branches took a superficial course within the subcutaneous fat and reached the nipple from the lateral side. These findings suggest that the nerves innervating the nipple and areola are best protected if resections at the base of the breast and skin incisions at the medial areolar border are avoided.