For 40 years the Intergovernmental Oceanographic Commission (IOC) has been the most important international body promoting understanding of ocean processes. Originating from a programme of UNESCO, in 1960 the IOC became a separate unit of UNESCO. The status of the IOC is regulated by Statutes which were substantially revised in 1999. These Statutes define the IOC as a part of UNESCO with functional autonomy limiting the authority of UNESCO bodies to supervise the IOC. This functional autonomy is reflected in the purposes and functions of the IOC, its relations with other international organisations and its own membership regulations. It is also reflected in its organisational structure, which consists of an Assembly, an Executive Council, a Secretariat and subsidiary bodies. The IOC is financed by UNESCO, with additional contributions allocated by Member States. The activities of IOC aim to improve our knowledge of the oceans and are increasingly directed towards the issues of responsible ocean management and sustainable development. The programmes are subdivided into ocean science projects, operational observing systems and ocean services. A special focus is training and education as well as mutual assistance in the field of ocean sciences as a contribution towards capacity building as a prerequisite for worldwide programmes. In performing its tasks the IOC enjoys partial autonomy under international law. However, its functional autonomy is considerably limited by the fact that programme and budget planning has to be approved by UNESCO, and that the funds and the personnel for the Secretariat are primarily provided by UNESCO. On the other hand it benefits from the facilities and opportunities offered from UNESCO so that the integration into this organisation and, simultaneously, the granting of a functional autonomy, constitutes a viable and economic way of promoting international co-operation with a view to improving our knowledge of the oceans.