The World Health Organisation (WHO) is a specialised agency of the United Nations with headquarters in Geneva. It was founded in 1948 and today has 194 member states. The aim of the WHO, as defined in its own constitution, is to raise health standards worldwide and to counteract existing inequalities in healthcare between states in order to achieve the best possible health for the members of all nations and thus to create a basis for worldwide "peace and security". The WHO's tasks for achieving optimal healthcare include, for example, the global coordination of disease control, support for the establishment and expansion of health systems in countries of the global south, the regular collection of global data on health and disease, and the expansion of global vaccination programmes and programmes relating to other health risk factors such as obesity, smoking or occupational stress.