The English Longitudinal Study of Ageing (ELSA) is a longitudinal study that collects multidisciplinary data from a representative sample of the English population aged 50 and older. The study started in 2002 and there are currently 7 waves of completed data and an eighth wave is currently being collected. The survey data are designed to be used for the investigation of a broad set of topics relevant to understanding the ageing process. Both objective and subjective data are collected covering themes such as health trajectories, disability and healthy life expectancy, the determinants of economic position in older age; the links between economic position, physical health, cognition and mental health; the nature and timing of retirement and post-retirement, labour market activity; household