The selection process in collection management has been characterized as based primarily on logical, rational thinking processes. Psychologists, however, M any of the most important decisions that are made in libraries involve collection development and management. Decisions about whether to add new titles or to cancel existing ones are often complicated and stressful because they frequently involve the commitment or redistribution of limited funds. Often the outcome of the decision affects not only librarians but also stakeholders outside the library. For academic libraries, these constituents include faculty, students, and sometimes the community. Decisions by public and school librarians are often made with parents, school boards, library trustees, and municipal officials in mind.Given its importance, librarians have attempted to analyze the process of decision making for collection development. This process has been depicted in the library literature as being a thoughtful, reasonable, rational one that is fundamentally logical and deliberative. Psychologists have examined decisionmaking processes in much more depth and detail than librarians. The psychological literature indicates that decision making is not simply a cognitive or thinking process. Rather, it depends to a significant extent on affect or emotion. The purpose of this paper is to examine the psychological research on decision making and explore the implications of revisioning collection development decisions as being not simply matters of the head but also matters of the heart. Standard works on collection development generally depict the selection process as a mental process but not an emotional one. Hamlin states that selection requires the selector to understand the needs of the user and know which resources to consult to locate appropriate material.1 The selector must be able to differentiate suitable sources from unsuitable ones, and evaluate the quality of the materials. The decision-making process also involves being able to reconcile the amount and cost of the material under consideration with the budget that the selector has to work with. A selector also needs to be aware of how much material the library already owns on a topic and whether further material is needed, and also if similar material may be available in a nearby collection. The selection process that Hamlin depicts is thus exclusively cognitive, with no reference to affect or emotion.