This course provides an introduction to the main theories of comparative political economy (CPE) and their explanations of variation of economic policies and outcomes. The survey of these theories is organized as a progression from micro- to macro-level explanations. We begin by examining the sources of political cleavages over various economic policies and the formation of political coalitions. Next, we explore a range of theories positing that differences in the organization of interest groups lead to systematic differences in economic outcomes. We examine how comparative political economists have studied the problem of ‘state capture’ by interest groups and its economic and political consequences. In the last part of the course, we apply these theories to a variety of issues, including financial development, taxation, the development of social welfare, and the political management of unemployment.