Underrepresentation of minority groups in the oncology physician workforce is a pressing issue that may contribute to disparities in cancer research, clinical care, and patient outcomes. To address this, we highlight the role of medical culture and institutions in perpetuating a range of barriers that lead to the persistent underrepresentation of minority medical trainees and physicians. These barriers include an exclusionary medical culture, bias in measures of merit, financial barriers to medical subspecialty training, underrecognition of achievement, and poor representation and satisfaction among underrepresented faculty. Furthermore, we suggest a more intentional approach to diversity that values both recruitment of underrepresented undergraduates and early medical students and retention of internal medicine trainees, hematology-oncology fellows, and faculty. To counteract deeply embedded structural racism that hampers diversity efforts, this multifaceted approach will require cultural transformation of our medical institutions at all levels, including increased institutional transparency, mandatory evidence-based bias training, acknowledgment of varied achievements, changes in recruitment practices, and reinvigoration of pipeline development programs with a focus on financial support. Taken in combination, programs should recognize the scope of deterrents to representation and develop program-specific, longitudinal interventions to promote more successful diversity initiatives within the field of oncology. The Oncologist 2021;26:630-634 Implications for Practice: The medical profession recognizes the value of physician workforce diversity in improving the quality of both medical education and patient care. In return, medical schools and training programs invest in recruitment programs focused on candidates who are underrepresented in medicine. In the field of oncology, where stark racial and ethnic disparities in care and health outcomes are well-defined, measures of minority physician representation remain especially stagnant. This study clearly defines the barriers that limit the effectiveness of such programs and provides recommendations to achieve the necessary workforce diversity in oncology.