has been Research Director of the Institute for Fiscal Studies (IFS), where he is also Director of the ESRC Centre for the Microeconomic Analysis of Public Policy. His research covers the empirical microeconomic study of consumer, savings and labour supply behaviour. He has developed new microeconometric tools for the study of dynamic panel data models and the nonparametric analysis of individual decisions. He has worked on a number of high profile policy reports mostly in his position as Research Director at the Institute for Fiscal Studies which is very influential in the economic policy debate in the UK. Most especially on personal tax reform, pension reform and the analysis of inequality. He was an editor and author of the Mirrlees Review of Tax Reform which reported its findings in 2011, with high profile presentations at the IMF, the EU and the UK Treasury.