Ian Deary is Professor of Differential Psychology at the University of Edinburgh. His principal research interest is human mental abilities, especially the origins of cognitive differences and the effects of ageing and medical conditions on mental skills. He has published over 300 refereed journal articles and three authored books, including Looking Down on Human Intelligence: From Psychometrics to the Brain, which won the British Psychological Society’s Book Award in 2002. Professor Deary leads a research team studying cognitive ageing by following up the people who took part in the Scottish Mental Surveys of 1932 and 1947. He and his collaborators have succeeded in tracing 550 survivors of the former and 467 of the latter, allowing within-subjects measures of changes in cognitive processing over 69 and 53 years. His expertise in the methods of differential psychology has given him a special and innovative edge in analytical approaches, such as factor analysis and structural equation modelling, and enabled him to identify sub groups within clinical populations and identify the associations between individual difference and disease variations. During 1999-2001 he was president of the Society for the Study of Individual Differences. He was elected as a fellow of the Royal Society of Edinburgh and the British Academy in 2003 and I am delighted to welcome him as a fellow of the Academy of Medical Sciences today.