Professor Diamond was appointed on 1 April 2010. He was previously Chief Executive of the Economic and Social Research Council (a position he continued to hold and devote 20% of his time to until 30 June 2010). He was also Chair of the Research Councils UK Executive Group (2004-2009) the umbrella body that represents all seven UK Research Councils. Before joining the ESRC Professor Diamond was Deputy Vice-Chancellor at the University of Southampton.

Professor Diamond graduated in1975 with a BSc (Econ) Honours from the London School of Economics and Political Science (LSE) followed in 1976 with an MSc Statistics also from the LSE. He then received his PhD in Statistics from the University of St Andrews in 1981. He began his academic career at Heriot Watt University in 1979 before joining the University of Southampton in 1980 where he was a lecturer, senior lecturer and Professor before being appointed Dean of Social Sciences in 1997 and then Deputy Vice-Chancellor in 2001.

A social statistician, Professor Diamond's work has crossed many disciplinary boundaries, most notably working in the area of population but also in health, both in the developed and less developed world, in environmental noise and with local authorities. His research has involved collaboration with many government departments including the Office for National Statistics, the Department for International Development, the Department of Transport and the Department for Work and Pensions.
Professor Diamond is Chair of the Lloyds TSB Foundation for England and Wales and a trustee of the World Wildlife Fund UK. He is a member of the Universities UK Research Policy Committee, Chair of the Universities UK Group on Efficiency, a member of the Scottish Science Advisory Council and a Board Member of the British Universities and Colleges Sport organisation. Professor Diamond was elected to the UK Academy of Social Sciences in 1999, is a Fellow of the British Academy (2005), a Fellow of the Royal Society of Edinburgh (2009) and holds honorary degrees from the universities of Cardiff and Glasgow.