Medicare is a nationwide health insurance program for the aged and certain disabled persons. Over its 32 year history, it has provided important protection for millions of Americans. However, the program is now facing a number of problems. The first and most pressing concern is whether Medicare's financing mechanism will be able to sustain it in the long run. Many people are also concerned that the program's structure, which in large measure reflects both the health care delivery system as well as political considerations in effect at the time of enactment, has failed to keep pace with the changes in the health care system as a whole. A related concern is whether the program's benefit structure adequately responds to the health care need of today's aged and disabled populations. This book addresses these and other related issues.