This course is designed to introduce doctoral students to theorization and its role in the research process. The emphasis in the course will be on understanding the fundamental challenges posed by social-scientific investigation and their relevance to conducting research on policy and practice. Cutting across the disciplines are two classic traditions in the philosophy of social science that approach questions of knowledge, observation, and causation differently. We will examine both naturalist and anti-naturalist conceptions of ontology, epistemology, theory, and method, as well as efforts to develop a third tradition based on "critical realist" or "historical" approaches, to construct three major paradigms of social inquiry. These paradigms present different strategies for making connections between such basic issues as problem definition, theory construction, research design, empirical investigation, and evaluation. Following this basic overview, the course will focus on three different paradigmatic approaches to a single social problem to more fully illustrate the contrasts and potential complementaries between the paradigms. Finally, we focus on how these paradigms address the theoretical challenges posed by two common modes of investigation: the case study and the comparative study. Neither a survey of social-scientific theories nor an introduction to research methods, this course examines multidisciplinary approaches to bringing theory to bear on the process of research. Readings will combine selections from the philosophy of social science, examples of scholarship that embody divergent strategies of investigation, and excerpts from the small body of useful work on "social inquiry" that reflects on the connections between the two.