This article introduces the seven specially commissioned papers in this special issue of Ageing & Society from the projects funded by the UK Economic and Social Research Council's Growing Older Programme. The ESRC Programme has been the largest single investment in social sciences research on ageing in the United Kingdom. It comprised 24 projects and, when operating at full capacity, 96 researchers. The article details the background to the Programme, its commissioning process, its eventual structure and how it operated. Then a selection is made of some of the ways in which the Programme has contributed new knowledge to social gerontology. No attempt is made to achieve comprehensive coverage of the Programme's topics but rather a selection is presented of the new insights generated under its six themes: defining and measuring quality of life, inequalities in quality of life, technology and the built environment, healthy and active ageing, family and support networks, and participation and activities in later life. The projects were spread unevenly across these themes but important new knowledge has been produced under each theme. The conclusion emphasises the scientific contribution of the Programme and especially the extent to which older people's own attitudes, aspirations and preferences have been at the forefront, but it questions whether or not policy makers and practitioners will use this major evidence base.