Accelerated partial breast irradiation (APBI) has been established as an alternative to whole breast irradiation (WBI) following breast-conserving surgery for select patients with early-stage breast cancer. In addition to lending greater patient convenience and a significant reduction in treatment time, APBI promotes normal tissue sparing and has demonstrated equivalent ipsilateral breast tumor recurrence (IBTR) and long-term toxic effects rates in selected patients.1 Whereas older trials comparing WBI with APBI used multicatheter brachytherapy, more recent phase 3 clinical trials have used alternative radiation therapy (RT) modalities, including 3-dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), and intraoperative radiation therapy (IORT) using low-energy photons or electrons. Of these alternative modalities, IORT yields the greatest reduction in treatment time—compared with standard external beam radiation therapy (EBRT) spanning several weeks, IORT may be completed in minutes during breast-conserving surgery. In addition, IORT has been shown to be significantly less costly than EBRT while producing similar quality-adjusted life years.2 Unfortunately, IORT has often been overlooked as a treatment option, and many clinicians remain skeptical of its efficacy even in the face of encouraging results.