Argues that management needs to be 'joined up', i.e. that it needs to acknowledge the interdependence of all parts of the organization and understand that strategy, structure and systems need to complement each other. Summarizes research into what is termed complementary change. Draws on work with BP and Unilever to discuss four aspects of complementary change - complementarities traps, complementarities gaps, the virtuous circles of complementary change and the J-curve (in which there is a short drop in performance followed by a steep rise).