This chapter introduces the key issues and prospects in the Madrid Plan of Action on Ageing which was adopted by the Second World Assembly on Ageing in Madrid from the 8 to 12 of April 2002. The Madrid Plan put forward a bold agenda that focused on three priority areas: older persons and development; advancing health and well-being into old age; and ensuring the existence of enabling and supportive environments. With 239 recommendations related to 35 objectives covering 18 issues consolidated under the priority areas above, the Madrid Plan remains a crucial comprehensive framework for the development of policies and programmes concerning population ageing and older people. This chapter traces how the Madrid Plan was crucial for transforming ageing welfare from a stand-alone issue or even simply an afterthought in national policies to one that is mainstreamed in disparate strands of social and health care strategies and programmes.