A decision maker may be concerned about the effects of his or her actions on other individuals. There may be altruistic or malevolent motives involved, but, since we prefer to think positively, we shall concentrate our attention on the prototypical higher-level, benevolent, executive decision maker. Let us refer to this individual decision maker simply as the “Decision Maker”—that person who wishes to incorporate the feelings, values, preferences, and Utilities of others into her own value assessments. She wants to make everyone happy but, alas, tradeoffs will have to be made. These concerns will be the subject matter of this chapter but before we delve into details, let us put this problem into a broader perspective: that of the group decision problem. We must be careful, however, since we believe there is no such thing as the group decision problem. We should talk in the plural about group decision problems.

From a descriptive point of view, as contrasted to a prescriptive point of view, most actions taken by decision makers, both private and public, can only be explained in terms of a panoply of various interacting forces and actions taken by many individuals acting through a mixture of motives. Just imagine how a bill gets through the U.S. Congress. This is truly a group effort.