The United Nations Environment Programme (UNEP) New York Office undertakes policy level inter-agency functions working to ensure effective United Nations system-wide cooperation and coordination in the field of environment, through specific inter-agency initiatives, and UNEP's proactive participation in and contribution to major inter-agency meetings (particularly the Administrative Committee on Coordination and its subsidiary bodies and the United Nations Executive Committees). The office also develops strategies and specific policy initiatives and proposals on inter-agency environment coordination issues, and provides policy development advice in this regard.

The office undertakes representation and liaison with respect to the Permanent Missions of United Nations Member countries in New York, United Nations organisations based in New York, and Departments of the United Nations Secretariat, including the Office of the Secretary-General. The office ensures effective and proactive UNEP contributions in relevant inter-governmental meetings, in particular the General Assembly and its subsidiary bodies, the Economic and Social Council and its subsidiary bodies (including the Commission on Sustainable Development), and other special intergovernmental events and conferences, through regular and systematic representation, and providing substantive reporting and policy analysis.

The office further undertakes outreach functions, developing and maintaining active contacts with non-governmental organisations, foundations, private sector corporations, academic institutions and other elements of civil society, building support among them for the work of UNEP, providing them with scientific and substantive information, and facilitating the transmittal of their views and information to UNEP's Headquarters in Nairobi and its outposted offices. The office also maintains a network of environmental media contacts within New York and the United Nations and ensures that environmental issues are featured and targeted to the right audiences, and that media attention is accorded to major issues and UNEP initiatives. The unit also serves as the focal point for UNEP contact with the United Nations Department of Public Information, and works closely with the Office of the Spokesman for the Secretary-General, and organizes special events and exhibits at United Nations Headquarters.