Public organizations are compound bodies characterized by competing endogenous dynamics of governance. This study makes two main contributions. First, it contributes to an organizational approach to studies of public policy and administration by conceptualizing compound agency governance. Second, by determining how variation in agency governance reflects endogenous organizational factors. Based on a study of the Norwegian Radiation and Nuclear Safety Authority (DSA), two observations are highlighted: Firstly, DSA staff are torn between two competing behavioural logics: A governmental and a transnational logic. Moreover, portfolios of core state powers are more closely monitored by parent ministries than portfolios that relate to non-core state powers. Secondly, the study suggests that organizational factors are vital determents in balancing behavioral logics in agency governance.