Many Americans do not have access to adequate medical care. Previous research on this problem focuses primarily on individual-level determinants of access such as income and insurance coverage. The role of community-level factors in helping or hindering individuals in obtaining needed medical care, however, has not received much attention. We address this gap in the literature by investigating the association between neighborhood residential instability and access to health care. Using individual-level data from the 2000 Medical Expenditure Panel Survey and block-group level data from the 2000 decennial census, we find that individuals who live in neighborhoods with high residential turnover have worse health care access than residents of other neighborhoods. This association persists even when the prevalence of poverty, the supply of health care, and a variety of individual characteristics are held constant. We offer explanations for these findings and suggest directions for future research. (Contains 3 notes and 3 tables.)