The COP, subsidiary bodies and Bureaux are serviced by a secretariat, whose mandate is laid out in general terms in Article 8 of the Convention. The main functions of the secretariat are to make practical arrangements for sessions of the Convention bodies, to assist Parties in implementing their commitments, to provide support to on-going negotiations and to coordinate with the secretariats of other relevant international bodies, notably the Global Environment Facility (GEF) and the Intergovernmental Panel on Climate Change (IPCC). Specific tasks of the secretariat include the preparation of official documents for the COP and subsidiary bodies, the coordination of in-depth reviews of Annex I Party national communications and the compilation of greenhouse gas inventory data. The greater technical work needed since the adoption of the Kyoto Protocol (e.g. on the mechanisms, methodologies and land-use change and forestry) is leading to a trend of increased technical expertise within the secretariat. The Convention secretariat will also serve the Protocol.

The secretariat is institutionally linked to the United Nations and administered under United Nations Rules and Regulations. It now employs some 100 staff from all over the world. Its head, the Executive Secretary, is appointed by the Secretary-General of the United Nations in consultation with the COP through its Bureau, and currently holds the rank of Assistant-Secretary-General. The Executive Secretary reports to the Secretary-General through the Under-Secretary-General heading the Department of Management on administrative and financial matters, and through the Under-Secretary-General heading the Department for Economic and Social Affairs on other matters. The present Executive Secretary, Michael Zammit Cutajar (Malta), has headed the secretariat since it was set up in 1991.

As a neutral body of international civil servants, the secretariat is accountable, through the Executive Secretary, to the COP and subsidiary bodies and carries out those tasks that fall under its mandate in the Convention and Programme Budget. The COP and subsidiary bodies will often request a specific assignment from the secretariat within this mandate, e.g. to prepare a background study on a particular issue. The secretariat is guided in its work by the Bureaux of the Convention bodies.

Since August 1996, the secretariat has been located in Bonn, Germany. It moved from its previous location in Geneva, Switzerland, following an offer from Germany to host the secretariat, which was accepted by COP 1.

Every two years, the Executive Secretary proposes a Programme Budget, setting out the main tasks to be performed by the secretariat in the coming biennium and the funding needed to carry out this work. This proposed Programme Budget is considered in the SBI, which then recommends a Programme Budget for approval by the COP. For the current biennium 2000-2001, the Programme Budget for the secretariat stands at around US$12 million per year, and is funded by contributions from Parties, their shares being based on the UN scale of assessment. The Government of Germany (the host country of the secretariat) provides a further annual contribution to offset planned expenditures, currently amounting to DM 1.5 million as well as an annual contribution of DM 3.5 million to support the costs of conference and meeting facilities and related requirements for events in Bonn (the "Bonn Fund"). Additional voluntary contributions also fund participation by developing countries (approximately US$1.8 million a year) and supplementary activities (averaging around US$3 million a year). The secretariat's structure is kept under review and modified to ensure that it responds to the changing needs of the climate change process.

The secretariat is currently organized into six programmes (see organigramme of the secretariat), each headed by a "Coordinator", whose main areas of responsibility are as follows:

Executive Direction and Management (EDM): EDM, the office of the Executive Secretary, supports the Executive Secretary in the overall management of the secretariat, in developing policies and in ensuring the coherence of the secretariat's work. The Executive Secretary gives advice to the Convention bodies and their Bureaux, and promotes partnerships with other organizations. The Executive Secretary is assisted by a Deputy, designated from among the Coordinators of the other programmes.

Science and Technology (S&T): S&T deals with the methodological, scientific and technological aspects of the Convention process, providing support to the SBSTA. Its tasks include developing methodologies to improve data accuracy, identifying options to promote the transfer of climate-friendly technologies, elaborating methodologies and tools for evaluating adaptation strategies and maintaining close contact with the IPCC. An important element of S&T's current work programme concerns the technical aspects of the Protocol, for example, the drafting of reporting guidelines and issues relating to carbon "sinks".

Implementation (IMP): IMP is at the frontline of assisting countries in implementing their commitments and is responsible for support to the SBI. IMP compiles and synthesizes National Communications and inventory data, coordinates In-Depth Reviews of Annex I Party National Communications, facilitates capacity-building activities for developing countries and ensures liaison with the Convention's financial mechanism (operated by the GEF). IMP is also responsible for supporting negotiations on a compliance system under the Protocol and on the vulnerability of developing countries to climate change and to mitigation measures.

Planning, Coordination and Emerging Issues (PCEI): This programme provides support to negotiations under the SBSTA and SBI on the design of the Kyoto Protocol mechanisms and has responsibility for the analysis of new and cross-cutting issues. It also supports the Executive Secretary in strategic planning, and in monitoring the coherence of the secretariat's substantive preparatory work for COP/MOP 1 (e.g. on compliance and reporting obligations). Another key task for PCEI is supporting the implementation of Activities Implemented Jointly (AIJ).

Intergovernmental and Conference Affairs (ICA): A core task of the secretariat is organizing sessions of the COP, subsidiary bodies and informal meetings such as workshops. ICA organizes the substantive agenda of the sessions of the COP, makes arrangements for COP Bureau meetings and supports the COP President. In addition, it finds suitable venues for the sessions of COP and subsidiary bodies, coordinates the production and dissemination of official documents and makes all the logistical arrangements for interpretation into the six UN languages, accrediting delegates and related services. Furthermore, ICA is responsible for relations with Parties, including the maintenance of a system of National Focal Points.

Information, Outreach and Administrative Services (IOAS): IOAS disseminates information on climate change and the Convention process, including official documents, data and public information products. A key aim of IOAS' work is to raise public awareness of climate change and build capacity in the secretariat and among Parties to network, exchange information and communication technologies. IOAS is active in forging links with other UN and intergovernmental bodies engaged in climate change-related work (e.g. the UN Environment Programme (UNEP), the UN Development Programme (UNDP), the UN Conference on Trade and Development (UNCTAD), the UN Industrial Development Organization (UNIDO), the Convention on Biological Diversity and the Convention to Combat Desertification). IOAS is also responsible for the administration and financial management of the secretariat, i.e. administering the financial resources and staff; liaising with the United Nations and the host Government on administrative matters.