Recent events indicate that Medicare Part C (Medicare Advantage) plans are poised to prosper. Yet many employers express hesitation to offer Medicare Advantage, formerly known as Medicare+Choice, plans to their retirees because they are concerned about the potential withdrawal of those plans if there is a reversal of federal funding rules. This article addresses those concerns. It provides a historical overview of Medicare Part C and describes the impact of the most recent agency guidance. The author cites plan trends, raises employer implications and concludes that Medicare Advantage plans will continue to expand, possibly facilitated by employers as they implement leading-edge retiree medical designs.