Kenneth Arrow is the Joan Kenney Professor of Economics and Professor of Operations Research, emeritus; a CHP/PCOR fellow; and an FSI senior fellow by courtesy. He is the joint winner of the Nobel Memorial Prize in Economics with John Hicks in 1972. To date, he is the youngest person to have received this award, at 51. In economics, he is a figure in post-World War II neo-classical economic theory. Many of his former graduate students have gone on to win the Nobel Memorial Prize themselves. His most significant works are his contributions to social choice theory, notably "Arrow's impossibility theorem", and his work on general equilibrium analysis. He has also provided foundational work in many other areas of economics, including endogenous growth theory and the economics of information. He has been co-editor of the Handbooks in Economics series since the mid-1980s.