Consumer researchers have long assumed that consumers' knowledge about product concepts is organized in an associative network structure. Recent advances in conceptual cognition have raised issues beyond the classical versus prototype or exemplar controversy by identifying theory-based concepts. This article reviews the current issues in conceptual cognition of frame theory, conceptual functions other than categorization, domain-specific kinds of concepts, feature centrality, and perceptual representation of concepts. In addition, the role of spatial diagrams is implicated in the problem of describing consumer knowledge structures. The articles in this special issue are introduced in this context. © 2002 Wiley Periodicals, Inc.