Starting from a brief literature review, this paper identifies key issues for future research in three related category management (CM) decision areas: assortment, shelf and stockout management. It elaborates on the interdependencies between the three CM issues, underscoring the need for a more integrated research approach. A common framework is presented of factors mediating and moderating consumer reactions to CM changes, which may provide guidelines for future research on reaction heterogeneity. The paper concludes with a discussion of the methodological challenges to be faced, ranging from advanced data collection procedures, over the development of more ingenious model structures, to the design of more powerful estimation and optimization routines. Copyright © 2005 John Wiley & Sons, Ltd.