Building on lecture notes from his course at Stanford University, James G. March provides an introduction to decision making, a central human activity, fundamental to individual, group, organizational, and societal life. March draws on research from all the disciplines of social and behavioral science to show decision making in its broadest context. By emphasizing how decisions are actually made — as opposed to how they should be made — he enables those involved in the process to understand it both as observers and as participants. In addition, March explains key concepts of vital importance to decision makers, such as limited rationality, history-dependent rules, and ambiguity, and weaves these ideas into a full depiction of decision making.