The recently established MRC Unit for Lifelong Health and Ageing (LHA) is the new home of the MRC National Survey of Health and Development (NSHD). The NSHD, the oldest of the British birth cohort studies, is unique in having data from birth to age 60 years on the health and social circumstances of a representative sample (N=5362) of men and women born in England, Scotland or Wales in March 1946. The mission of the Unit is to realise the scientific potential of the NSHD as a world class, interdisciplinary life course study of ageing