All of the essays in this new collection by Thomas Schelling convey his unique perspective on individuals and society. This perspective has several characteristics: it is strategic in that it assumes that an important part of people's behavior is motivated by the thought of influencing other people's expectations; it views the mind as being separable into two or more parts (rational/irrational; present-minded/future-minded); it is motivated by policy concerns--smoking and other addictions, global warming, segregation, nuclear war; and while it accepts many of the basic assumptions of economics--that people are forward-looking, rational decision makers, that resources are scarce, and that incentives are important--it is open to modifying them when appropriate, and open to the findings and insights of other social science disciplines. Schelling--a 2005 Nobel Prize winner-- has been one of the four or five most important social scientists of the past fifty years, and this collection shows why.