Globalisation's unprecedented growth and transborder activities of business coupled with increasing awareness of the impact of business on societies and human rights has resulted in demands for the international society to regulate corporate social and human rights responsibilities. This not only challenges traditional notions of duty bearers under international law, but also calls for novel approaches for the United Nations (UN) to implement central parts of the Charter's human rights aims and to address corporate behaviour in a state-centred international law-making order that lacks the willingness of States to regulate business. This article explores recent UN responses and argues that in the absence of States acting through ordinary international law-making, the UN as an intergovernmental organisation draws on participatory modes of law-making and new forms of law in order to normatively influence businesses' impact on human rights. The pattern of using these forms suggests an institutionalisation of reflexive regulation as a regulatory process drawing on public-private regulation, and of an emerging UN based 'Global Administrative Law' in order to meet regulatory challenges in living up to the human rights aims embodied in the UN Charter under the conditions posed by globalisation of the economy and emergence of strong transnational non-state actors. The analysis is based on the UN Global Compact, the draft Norms on the Responsibilities of Transnational Corporations and Other Business Enterprises with regard to Human Rights and the process of the Special Representative of the Secretary General on the issue of human rights and transnational corporations and business (SRSG).