Experienced politicians and legislators have always known that by shaping the agenda they can influence decisions. In the past, experienced politicians' knowledge has been mostly anecdotal. The development of social choice theory provides a basis for a fuller and more systematic understanding of the effects of agendas on outcomes. In this book, the appreciation of the role and workings of agendas that has been developed using social choice theory is presented in a nontechnical way. This collection of essays explores several features of agenda formation by developing ideas such as that most issues are one-dimensional, agenda items and issues are certain to change because losers have an interest in changing them, domestic concerns at least partially determine agendas and issues in international politics, and new issues and arguments can abruptly change the expectations about winning. The distinguished contributors argue that the knowledge needed to compete includes knowing what the possible agenda items or issues are, where they come from, and how to manipulate them advantageously.