The problemMedical schools require highly skilled and committed clinical faculty to teach, assess, supervise and mentor students' clinical care. Medical education is facing a crisis in recruiting and sustaining these clinical teachers. Faced with multiple demands and responsibilities in fast‐paced clinical environments, teachers may not have the time, resources or stamina to sustain these critical roles. Medical school leaders must commit to and provide structures and processes to attract, sustain and retain clinical teachers.Conceptual frameworkThe authors use the lens of self‐determination theory to frame approaches to support teacher sustainability. Self‐determination theory describes sources of human motivation. The theory and its evidence base characterise three human psychological needs: autonomy, competence, and relatedness. This theory can bridge individual psychological and institutional leadership perspectives to help medical school leaders anticipate and respond to their clinical teachers' needs. The authors propose three practical steps: practices to advance employee‐centredness, processes to align individual and institutional values, and restructuring education to support clinical teachers' needs alongside student and patient needs. The authors describe limitations to this relational approach that focuses on leadership actions and consider individual agency as another key factor for sustainability.DiscussionMedical school leaders can develop and apply theory‐driven approaches to advance sustainability. Sustainability now and in the future requires careful attention to the needs of clinical teachers and to their relationships with and within medical schools.