This chapter discusses various past and future aspects of the global economy. There has been a huge transformation of the global economy in the last several years. Articles on the future of energy in the global economy by Jeffrey Ball and on measuring inequality by Jonathan Ostry and Andrew Berg are also illustrated. Since the 2008 global crisis, global economists must change the way they look at the world.

Recent developments in public economics have largely been in the direction of reaffirming the limits of the market and of establishing new ones. The possible existence of fundamental non-convexities, imperfect and asymmetric information, incentive compatibility, imperfect competition, strategic complementarity, and scale economies led to the conclusion that a large set of market failures exist; such situations also imply government failure. Acocella, considers this complicated picture and provides a discussion of the different approaches to establishing social 'rankings' of the possible situations and the underlying principles. The arguments for and against different institutions are then analysed at a micro and macroeconomic level. The market and the government are recognised as imperfect, and thus complementary, institutions. Specific policy targets and instruments are considered in the areas of micro and macro-economic policy. Special attention is devoted to questions of policy management in an open economy. Finally, problems of domestic and international policy co-ordination are considered.

The literature on the theory of social choice has grown considerably beyond the few items in existence at the time the first edition of this book appeared in 1951. Some of the new literature has dealt with the technical, mathematical aspects, more with the interpretive. My own thinking has also evolved somewhat, although I remain far from satisfied with present formulations. The exhaustion of the first edition provides a convenient time for a selective and personal stocktaking in the form of an appended commentary entitled, 'Notes on the Theory of Social Choice, 1963, ' containing reflections on the text and its omissions and on some of the more recent literature. This form has seemed more appropriate than a revision of the original text, which has to some extent acquired a life of its own.

Leading economists address the ongoing challenges to economics in theory and practice in a time of political and economic crises. More than a decade of financial crises, sovereign debt problems, political conflict, and rising xenophobia and protectionism has left the global economy unsettled and the ability of economics as a discipline to account for episodes of volatility uncertain. In this book, leading economists consider the state of their discipline in a world of ongoing economic and political crises. The book begins with three sweeping essays by Nobel laureates Kenneth Arrow (in one of his last published works), Amartya Sen, and Joseph Stiglitz that offer a summary of the theoretical foundations of modern economics—the twin pillars of general equilibrium theory and welfare economics. Contributors then turn to macroeconomic stabilization and growth and, finally, new areas of research that depart from traditional theory, methodology, and concerns: climate change, behavioral economics, and evolutionary game theory. The 2019 Nobel Prize laureates, Abhijit Banerjee, Esther Duflo, and Michael Kremer, contribute a paper on the use of randomized control trials indevelopment economics. Contributors Philippe Aghion, Ingela Alger, Kenneth Arrow, Abhijit Banerjee, Kaushik Basu, Lawrence Blume, Guillermo Calvo, Francesco Caselli, Asli Demirgüç-Kunt, Shantayanan Devarajan, Esther Duflo, Samuel Fankhauser, James Foster, Varun Gauri, Xavier Gine, Gäel Giraud, Gita Gopinath, Robert Hockett, Karla Hoff, Ravi Kanbur, Aart Kraay, Michael Kremer, David McKenzie, Célestin Monga, Maurice Obstfeld, Hamid Rashid, Martin Ravallion, Amartya Sen, Luis Servén, Hyun Song Shin, Nicholas Stern, Joseph Stiglitz, Cass Sunstein, Michael Toman, Jörgen Weibull

Kenneth Arrow's pathbreaking Òimpossibility theoremÓ was a watershed in the history of welfare economics, voting theory, and collective choice, demonstrating that there is no voting rule that satisfies the four desirable axioms of decisiveness, consensus, nondictatorship, and independence. In this book, Amartya Sen and Eric Maskin explore the implications of ArrowÕs theorem. Sen considers its ongoing utility, exploring the theoremÕs value and limitations in relation to recent research on social reasoning, while Maskin discusses how to design a voting rule that gets us closer to the idealÑgiven that achieving the ideal is impossible. The volume also contains a contextual introduction by social choice scholar Prasanta K. Pattanaik and commentaries from Joseph E. Stiglitz and Kenneth Arrow himself, as well as essays by Sen and Maskin outlining the mathematical proof and framework behind their assertions.