WHO collaborating centres are institutions such as research institutes, parts of universities or academies, which are designated by the Director-General to carry out activities in support of the Organization's programmes. Currently there are over 800 WHO collaborating centres in over 80 Member States working with WHO on areas such as nursing, occupational health, communicable diseases, nutrition, mental health, chronic diseases and health technologies.

The idea of using national institutions for international purposes dates back to the days of the League of Nations, when national laboratories were first designated as reference centres for the standardization of biological products. As soon as WHO was established, it appointed more reference centres, starting in 1947 with the World Influenza Centre in London for worldwide epidemiological surveillance.

As early as 1949, the Second World Health Assembly laid down the policy (which has been constantly followed since) that the Organization should not consider "the establishment, under its own auspices, of international research institutions" and the "research in the field of health is best advanced by assisting, coordinating and making use of the activities of existing institutions".

All WHO collaborating centres, irrespective of their type of work, have been designated under that policy, which has undoubtedly enhanced national participation in the Organization's activities.