The article starts with the observation that there are overlaps in, so far, largely unrelated research programs concerned with the legalization in international relations, on the one hand, and transnational regulation and governance, on the other. The analysis of the literature at the interface between the “fourth strata of the geology of international law” and the “governance in the age of regulation” literatures reveals a substantial common interest in structures of transnational regulatory governance. At the same time, the theoretical toolkit of both strands of literature does not match the task of coping analytically with structures and processes in the overlapping realm. To sharpen the analytical edge, the article elaborates hierarchy, market, community, and design as four ideal types of control modes in transnational regulatory spaces. The application of this model to the empirical analysis of a number of regimes underpins the observation that control frequently occurs in hybrid regulatory constellations involving public and private actors across national and international levels. A key example concerns the prominence of domestic regulatory regimes in underpinning transnational governance processes, where national rules achieve extraterritorial effect as much through competitive as through hierarchical mechanisms.