Utilizing the theoretical framework of transnational legal orders (TLOs), this article treats two master questions in global governance: what are the limits to the power of the UN Security Council? Can norms of rule-of-law constrain UNSC powers? First, we outline a research design with emphasis on its documentary and unique internal empirical sources. Second, we sketch an interpretive narrative of UNSC engagement from the early 1990s to the present with ROL in three areas of UNSC action: peacekeeping, sanctions, and force. Third, we offer a new conceptual approach by proposing that ROL in the UNSC manifests itself in three dimensions: discourse; procedure (or rules); and structures. These dimensions come into play both internally, within the UNSC itself, and externally, to ROL institution-building in and between states, as well as in post-conflict zones, with a rather gray area between (e.g., when the UN peacekeeping missions are themselves subject to ROL oversight for the behavior of their personnel). Fourth, we examine the emergence of micro-TLOs under construction within the UNSC itself. We conclude with reflections on the potential for empowering elected members of the UNSC and weaker states in the UN to press ROL norms on the UNSC as a springboard for ROL global governance via the UNSC.