This book reviews recent trends, reforms and lessons learned in the 29 OECD countries as they relate to ageing. Recent reforms have been driven mainly by fiscal factors - to adjust systems such as pensions and long-term care to the ageing of the baby boom generation. This remains a main concern in many countries. A new reform agenda is emerging, however, that marries fiscal objectives with broader social and economic policy goals. It focuses on active ageing, providing opportunities and incentives for people to contribute more actively in the labour market and society as they grow older. This involves slowing, or reversing, trends towards ever-longer periods of time spent in retirement. This agenda is associated with likely trends towards a more diversified system of retirement income in most OECD countries - with more reliance on private pensions and a likely increase of earnings as a source of income among older people. Familiar policy debates -- such as the balance between public and private pensions -- may need to be recast to take account of the likely future growth in the role of earnings in the retirement income system. Interesting new questions arise. In the longer-term future, what should be the role of government policy in influencing the balance between work and leisure in older years? What priority should be attached to policies that support very long periods of passivity in the last third of life?