When one thinks about how collective decisions are made, voting is the method that comes naturally to mind. But other methods such as random process and consensus are also used. This book explores just what a collective decision is, classifies the methods of making collective decisions, and identifies the advantages and disadvantages of each method. Classification is the prelude to evaluation. What are the characteristics of a method of making collective decisions, the book asks, that permit us to describe a collective decision as good? The second part of the book is detailed exploration of voting: the dimensions in which voting situations differ, the origins and logic of majority rule, the frequency of cycles in voting, the Arrow and Gibbard-Satterthwaite theorems, criteria for ways of cutting through cycles and the application of these criteria to a variety of rules, voting over continuums, proportional representation, and voting rules that take account of intensities of preferences. Relatively unknown methods of voting give voting a much greater potential than is generally recognized. Collective Decisions and Voting is essential reading for everyone with an interest in voting theory and in how public choices might be made.

Publication of the Handbook of Group Decision and Negotiation marks a milestone in the evolution of the group decision and negotiation (GDN) eld. On this occasion, editors Colin Eden and Marc Kilgour asked me to write a brief history of the eld to provide background and context for the volume. They said that I am in a good position to do so: Actively involved in creating the GDN Section and serving as its chair; founding and leading the GDN journal, Group Decision and Negotiation as editor-in-chief, and the book series, “Advances in Group Decision and Negotiation” as editor; and serving as general chair of the GDN annual meetings. I accepted their invitation to write a brief history. In 1989 what is now the Institute for Operations Research and the Management Sciences (INFORMS) established its Section on Group Decision and Negotiation. The journal Group Decision and Negotiation was founded in 1992, published by Springer in cooperation with INFORMS and the GDN Section. In 2003, as an ext- sion of the journal, the Springer book series, “Advances in Group Decision and Negotiation” was inaugurated.

Individual decision making can often be wrong due to misinformation, impulses, or biases. Collective decision making, on the other hand, can be surprisingly accurate. In Democratic Reason, Hélène Landemore demonstrates that the very factors behind the superiority of collective decision making add up to a strong case for democracy. She shows that the processes and procedures of democratic decision making form a cognitive system that ensures that decisions taken by the many are more likely to be right than decisions taken by the few. Democracy as a form of government is therefore valuable not only because it is legitimate and just, but also because it is smart. Landemore considers how the argument plays out with respect to two main mechanisms of democratic politics: inclusive deliberation and majority rule. In deliberative settings, the truth-tracking properties of deliberation are enhanced more by inclusiveness than by individual competence. Landemore explores this idea in the contexts of representative democracy and the selection of representatives. She also discusses several models for the "wisdom of crowds" channeled by majority rule, examining the trade-offs between inclusiveness and individual competence in voting. When inclusive deliberation and majority rule are combined, they beat less inclusive methods, in which one person or a small group decide. Democratic Reason thus establishes the superiority of democracy as a way of making decisions for the common good.

This book provides a practical guide to how groups of people, everywhere, from the local village council to the United Nations Security Council, can best make collective decisions. By comparing the many voting procedures used in democratic decision-making, it explains why win-or-lose binary voting can be inaccurate and divisive, while the more inclusive preferential points system of voting can be so much more accurate and, therefore, more democratic; indeed, it is a win-win methodology. The text, essential reading for anyone interested in fair and participatory collective decision-making, also compares the most common electoral systems.

Every day thousands of decisions are made by all kinds of committees, parliaments, councils and boards by a 'yes-no' voting process. Sometimes a committee can only accept or reject the proposals submitted to it for a decision. On other occasions, committee members have the possibility of modifying the proposal and bargaining an agreement prior to the vote. In either case, what rule should be used if each member acts on behalf of a different-sized group? It seems intuitively clear that if the groups are of different sizes then a symmetric rule (e.g. the simple majority or unanimity) is not suitable. The question then arises of what voting rule should be used. Voting and Collective Decision-Making addresses this and other issues through a study of the theory of bargaining and voting power, showing how it applies to real decision-making contexts.

In The Origins of Collective Decision Making, Andy Blunden identifies three paradigms of collective decision making – Counsel, Majority and Consensus, discovers their origins in traditional, medieval and modern times, and traces their evolution over centuries up to the present. The study reveals that these three paradigms have an ethical foundation, deeply rooted in historical experiences. The narrative takes the reader into the very moments when individual leaders and organisers made the crucial developments in white heat of critical moments in history, such as the English Revolution of the 1640s, the Chartist Movement of the 1840s and the early Civil Rights Movement of the 1960s. This history provides a valuable resource for resolving current social movement conflict over decision making.

Most theories of elections assume that voters and political actors are fully rational. This title provides a behavioral theory of elections based on the notion that all actors - politicians as well as voters - are only boundedly rational.