Purpose of Review <p>This review explores recent findings concerning racial and ethnic disparities in radiation therapy (RT) for breast cancer. It highlights variations in treatment access, delivery, adverse effects, and outcomes, aiming to inform interventions that promote equity.</p> Recent Findings <p>Disparities persist in the receipt of RT following breast-conserving surgery, particularly among Black, Hispanic, and American Indian/Alaskan Native women. These groups are more likely to experience delays in care, higher rates of treatment noncompletion, and underrecognized side effects. Furthermore, differences in mean radiation dose and limited access to advanced RT techniques contribute to increased toxicities. Institutional, systemic, and interpersonal factors underlie these inequities.</p> Summary <p>Mitigating disparities in RT for breast cancer requires comprehensive strategies—expanding access, culturally sensitive care, dose optimization, and improved communication. Evidence from initiatives like the Michigan Radiation Oncology Quality Consortium (MROQC) demonstrates how data-driven quality improvement can narrow equity gaps.</p>