Description: There have been a variety of proposals related to expanding eligibility for Medicare, ranging from a publicly funded program to a full buy-in option. This session will explore the actuarial implications of various buy-in proposals and the potential impact that such policy changes could have on the health care market landscape. In particular, we will discuss the ways in which program eligibility requirements, plan designs, provider reimbursement arrangements, network design, rating rules, and subsidies could affect premium levels and membership volume in a Medicare buy-in market, as well as the potential side effects on providers and existing health care markets.