AIR estimated the financial impact of selected Medicare policy changes on Medicare Parts A, B, C, and D with a grant from the Commonwealth Fund. AIR developed a micro-simulation model to project the impact of policy options on beneficiaries’ future cost-sharing requirements, out-of-pocket costs, and premiums, and on Medicare program solvency. AIR presented the findings of these analyses in three policy briefs which informed leaders and policy makers on how changes in Medicare would affect the program’s sustainability and individuals’ access to care.