The introduction explains what imaginative culture is and why it matters. Imaginative culture-the subjects traditionally studied in the humanities-is that part of culture that consists in shared and transmissible mental experiences that are aesthetically and emotionally modulated. Such experiences include religion, ideology, and the arts. Evolutionary cultural theory has heretofore concerned itself mostly with technology and social organization. Imaginative culture is the last major piece in the puzzle of human nature. After describing the historical and disciplinary context for this volume and summarizing its contents, the introduction describes a toolkit of concepts and methods used by the authors in this volume: Tinbergen’s four categories of ethological analysis (phylogeny, ontogeny, mechanism, and adaptive function), cross-species comparison, cross-cultural comparison, and the psychology of individual identity. Under the category “mechanism, " subheadings include neuroscience, cognitive psychology, and the psychology of emotion. These concepts and methods are used as categories for describing subjects, observations, and arguments in the various chapters of the volume. “Directions for Further Research” identifies subject areas that have as yet received little attention from evolutionary scholars and scientists, describes opportunities for interdisciplinary collaborative research, and discusses the tension between institutional disciplinary inertia and the impulses of advancing knowledge.