Recent studies have demonstrated the possibility of identifying the sentinel lymph node (sN) as a reliable predictor of axillary lymph node status in both cutaneous melanoma and breast cancer. However, some important issues need further definition: (1) optimization of the technique for intraoperative detection of the sN; (2) predictive value of the sN as regards axillary lymph node status, and (3) reliability of intraoperative histology of the sN. We report our experience in sN mapping in patients with Stage I-II breast cancer, with the aim of assessing: (1) the feasibility of lymphatic mapping with a combined approach (vital blue dye lymphatic mapping and radioguided surgery); (2) the agreement of the intraoperative histologic examination of the sN, by means of hematoxylin and eosin staining with final histology, and (3) the accuracy of sN histology as a predictor of axillary lymph node status.