Theory and Practice as Capital argues that International Relations needs to add a sociological approach geared to understanding different types of practices, in order to be able to engage with the theory/practice question beyond philosophical statements.The book translates the abstract question of theory and practice into an empirical question of specific types of scientific practices. It shows they are linked to political practice in specified fields.Drawing on the work of Pierre Bordieu, the book reformulates the history and practice of European security, and gives new insights into the relationships between theory, practice, science and policy. Theory as Practice and Capital will be of interest to students and scholars of interntional relations, security studies and critical theory.