Adam Wagstaff is Research Manager in the Development Research Group (Human Development). He holds a DPhil in economics from the University of York and, before joining the Bank, was a Professor of Economics at the University of Sussex. He was an associate editor of the Journal of Health Economics for 20 years and has published extensively on a variety of aspects of the field, including health financing and health systems reform; health, equity and poverty; the valuation of health; the demand for and production of health; efficiency measurement; and illicit drugs and drug enforcement. Much of his recent work has been on health insurance, health financing, vulnerability and health shocks, and provider payment reform. He has extensive experience of China and Vietnam but has worked on countries in Africa, Latin America, South Asia, and Europe and Central Asia, as well as other countries in East Asia. Outside health economics, he has published on efficiency measurement in the public sector, the measurement of trade union power, the redistributive effect and sources of progressivity of the personal income tax, and the redistributive effect of economic growth.