Congress enacted legislation in 1990 that dramatically changed the rules for selling supplemental health insurance, or “Medigap” policies, to the elderly. Most notably, policy coverage was standardized. Insurance carriers are allowed to sell only the ten specified packages of benefits, which reduces consumer choice but facilitates comparison shopping. This legislation is important in its own right and also offers lessons for U.S. health care reform. To examine the changes brought about by this legislation and analyze their implications for health care reform, we conducted site visits to nine states and interviewed insurer representatives, executive branch officials, congressional staff, and various interest groups for two years.