There are vast disparities in access to healthcare across the United States, contributing to poor health outcomes. Up to eighty million individuals live in federally designated health professional shortage areas. Visa waiver programs were introduced to address physician shortages by granting work authorization to international medical graduates in exchange for a three-year commitment to practice in shortage areas. We are the first to study the effects of these programs on local physician supply and health outcomes. Focusing on Appalachia, we use proprietary data on all primary care physicians (PCPs) awarded visa waivers between 1999 and 2022, combined with Medicare claims data, to show that the arrival of a foreign PCP increases net physician supply. While initial gains are driven by visa waiver recipients, many of whom leave after three years, replacement by other PCPs keeps supply stable. We also find increases in healthcare utilization, especially ER visits, preventive testing and imaging, and cardiovascular procedures. Higher utilization increases diabetes and hypertension diagnoses among the previously undiagnosed, mirroring predicted rates of undetected cases among older adults. Foreign physicians thus play a critical role in providing care in medical deserts.