The study of hybrid public recruitment and GFCs has foundations in many different disciplines, including sociology, political science, economics, Public Administration, legal studies and historical science, some of which are relevant for this study. The research on recruitment itself has roots in sociology, specifically elite and career studies, while the role of commissioners is often examined from a historical point of view, since commissioners in different forms have been a consistent feature of different regimes including Prussia and the Third Reich. To bridge these disciplines, this study employs the economic-based viewpoint of rational-choice institutionalism and its principal-agent theory as the lens for the first, theoretical research objective about recruitment for hybrid institutions in general, and builds on previous legal and political science research on commissioners and commissioning, especially in Germany, for the second, empirical research objective about GFCs specifically.