This AARP insight on the issues, written by Lynn Nonnemaker of AARP's Public Policy Institute, examines Medicare's financial support for graduate medical education (GME), provides key data points regarding medical residency training, and identifies important policy issues regarding that financing. How many residents should Medicare fund? To what extent should Medicare GME funding be used to advance workforce policy? For what kinds of training should Medicare pay? The insight also looks ahead to possible changes to the way Medicare finances GME that may result from health reform and new proposals for restructuring Medicare's GME funding.