Ha lavorato in diverse aree della teoria economica come la teoria dei giochi, l'economia degli incentivi e la teoria dei contratti. In particolare, è noto per i suoi articoli sulla teoria dell'allocazione delle risorse e delle loro dinamiche. I suoi attuali progetti di ricerca includono i diversi sistemi elettorali, le loro iniquità e lo studio della formazione delle coalizioni.
Social choice on restricted domains, Harvard University Press, 1976.
The existence of economic equilibria: continuity and mixed strategies, coautore Partha Dasgupta, Stanford, Stanford University, 1977.
The implementation of social choice rules, coautori Partha Dasgupta e Peter J Hammond, Colchester, University of Essex. Dept. of Economics, 1978.
On the difficulty of attaining distributional goals with imperfect information about consumers, coautore Jean-Jacques Laffont, Bonn, Univ. Bonn, 1978.
An equilibrium analysis of search and breach of contract, coautore Peter A Diamond, Coventry, University of Warwick, 1978.
Rational expectations with market power: the paradox of the disadvantageous tariff on oil, coautore David M. G. Newbery, Cambridge, Mass., Massachusetts Institute of Technology, 1978.
A theory of dynamic oligopoly, coautore Jean Tirole, Stanford, Calif., Stanford University, 1983.
Input versus output incentive schemes, coautore John Riley, Cambridge, Mass., Harvard Institute of Economic Research, 1985.
Disadvantageous oil tariffs and dynamic consistency, coautore David M. G. Newbery, Cambridge, University of Cambridge, 1986.
On the fair allocation of indivisible goods, Cambridge, Mass., Harvard Institute of Economic Research, 1986.
Implementation and renegotiation, coautore John Moore, London School of Economics and Political Science, London, 1987.
Incentives, information, and organizational form, coautori Yingyi Qian e Chenggang Xu, Cambridge, Mass., Harvard Institute for International Development, 1998.
Nash equilibrium and welfare optimality, Cambridge, Mass., Harvard University, 1998.
Recent developments in game theory, Cheltenham, UK; Northampton, Mass., USA, Edward Elgar Publishing, 1999.
Auctions and efficiency, Princeton, Institute for Advanced Study, 2001.