Affirmative action is under increasing scrutiny. In medicine, the observation that minority physicians disproportionately serve minority patients has been one rationale for affirmative action. Using two large physician surveys, we find that minority and women physicians are much more likely to serve minority, poor, and Medicaid populations. Weaker, but significant association exists between physician and patient socioeconomic background. Service patterns are sustained over time and are generally consistent with physician career preferences. Ending affirmative action in medicine may imperil access to care. Results do not support affirmative action based on economic disadvantage instead of race, ethnicity, and sex.