To achieve that mission, all doctoral students are required to develop advanced knowledge and expertise in three interrelated areas: a) a substantive area of social welfare; b) social and behavioral science knowledge applicable to the substantive area; and c) research methods. Expertise in a substantive area of social welfare provides the foundation for advanced research in that area; social and behavioral science knowledge provides the theory and the empirical findings needed to understand the causes, dynamics and outcomes of the subjects and processes addressed by social welfare; and research competence is necessary to conduct the empirical research needed to advance knowledge.