In recent years, fiduciary law has increasingly moved to the center of scholarly attention in the common law world. Even a cursory review shows ample evidence of the importance of fiduciary-related norms; not only both in common law and civil law jurisdictions, but also beyond the nation state. Although civil law countries have no tradition of the trust as a legal institution, courts and scholars alike term relationships based on some kind of personal or professional trust “fiduciary”. Additionally, the trust as a legal institution is gaining ground in civil law countries, either following a national recognition of the Hague Trust Convention (e.g., Italy, the Netherlands) or because they have introduced trust legislation (Japan and other countries in East Asia). A number of more sector-specific rules and regulations issued by institutions and initiatives such as the OECD Principles of Corporate Governance and the UN report on “Fiduciary Duty for the 21st Century” are shaping legal norms and legislation. In other areas of the law with regulations and rules spreading beyond the nation state, scholars have been trying to spell out a concept of “transnational law”, determined to embrace the notion of “something being there” which doesn’t quite fit the bill of the traditional dichotomy of national law or international law. Given the phenomena described above, the question driving this Article is subsequently: Is there such a thing as transnational fiduciary law? Answering this question and mapping a research agenda proves to be a thorny issue, however. Not only is fiduciary law itself “elusive”. The same is true for transnational law and transnational legal theory. Methodologically, this makes thinking about transnational fiduciary law a daunting task. Grappling with all these issues, this Article aims to make a twofold contribution: First and foremost, it tries to lay a ground stone for transnational fiduciary law as a field, existing at the intersection of transnational law and fiduciary law. Second, it expands both transnational law and fiduciary law by establishing new perspectives on both fields. It explores how transnational law may evolve out of national norms. Additionally, the Article shows the possibility of crossing the common law-civil law divide in fiduciary law and demonstrates that, compared to the traditional common-law view, the fiduciary duty of loyalty may develop different kinds of distinctiveness in transnational settings. It builds on two main examples: horizontal transnational ordering of the trust in East Asia and vertical ordering of fiduciary law with respect to standards and principles concerning environmental, social and governance (ESG) issues.