Many demographers are already familiar with the British Household Panel Survey (BHPS), conducted from 1991 forward (Buck et al. 1994). The BHPS has been heavily used by researchers within and outside the United Kingdom (UK) and by government departments, resulting in more than 150 publications per year. The potential for scientific advance has led to the UK Household Longitudinal Survey- (UKHLS). This new survey was modeled on the BHPS and is the largest and most ambitious panel survey in the world. We describe this new social and health survey and some of the opportunities it offers for research in demography and health.