Preoperative injection of technetium-99 m sulfur colloid (Tc-99) in the Nuclear Medicine Department for localizing sentinel lymph nodes (SLNs) can be extremely painful for the patient. The difficulties in scheduling and the delay in starting surgery can be frustrating for the patient and the surgeon. We hypothesized that intraoperative injection facilitated by the subareolar technique would obviate the problems associated with preoperative injection.