By 2030, when most American baby boomers will have retired, all the large industrial economies will see a massive increase in the old age population. This book examines population aging and its implications for public retirement programs in the five largest industrial economies - Britain, France, Germany, Japan, and the United States. The authors report on national demographic trends, examine the current living conditions of the aged population, explain the structure of the retirement system, and estimate future budgetary costs of the public programs. They also discuss national debates over the potential reform of public retirement systems.