This chapter discusses the sources of change (dissatisfaction with outcomes, new states of the environment, access of new elites to power, etc.). We consider the extent of system change (partial, comprehensive), its suddenness (revolutionary, evolutionary), and, in the case of evolutionary change, the various ways in which it may be brought about (by the decisions of ruling government organizations affecting entire sectors of the economy, by decisions limited to intraorganizational rules). Next, we analyze the components of the system that are affected by the change (decision making, information, motivation). We examine the transition problems from one integrated system to the other, including the legacies of the old system and the obstacles it may place to the institution of the new, and the interdependence between policies and system change. We conclude with some observations based on the disparate strands of evidence on the feasibility of successful system change discussed in the body of the chapter.