Background: A recent study of Medicare claims data suggested that 20% of oncologists left clinical roles in the last ten years. This exodus will add substantial indirect and direct costs to the healthcare system and reduce access to care. Understanding contributing factors can lead to solutions to this exodus. Methods: We performed a qualitative study of medical oncologists who recently left or self-identified as considering leaving clinical practice. Six focus groups were conducted from January and March 2023 with 26 oncologists. We used the whole-of-person workforce retention framework to inform the focus group guide. Focus groups were recorded and transcribed. Recordings were analyzed with open coding and grounded theory approach. Results: 26 participants participated in six focus groups: well-balanced for gender (14 male, 12 female), career stage (5 early, 14 mid, 7 late), practice setting (19 academic, 7 private practice), and predominantly urban (25) and one rural. Thematic saturation was achieved in these six focus groups, with 5 major themes identified: Value, Career development/impact, Burnout, Work life balance and Workload. Participants in all six focus groups reported feeling undervalued due to a lack of recognition for uncompensated effort, including education and clinical research, inadequate resources to provide clinical care, and/or mismatch of values. Symptoms of burnout, lack of work/life balance, and unsustainable workloads were present. Administrative tasks, documentation, electronic medical records, and prior authorization were not identified as significant contributors. Many respondents hoped to someday return to clinical care. Conclusions: Themes of value, balance, and personal impact in the field were identified as major reasons oncologists left or considered leaving clinical care roles. We found that burnout is a symptom of dysfunction in the healthcare system and not due to a lack of personal resiliency. Medical organizations like ASCO should focus on improving the workplace environments by helping sites to focus on valuing clinical care, education, research, and right-sizing oncology practices to support excellent cancer care and support medical oncology workforce.