Since the establishment of the United Nations, various intergovernmental agreements and international human rights instruments have expressed the ambition of achieving social development, which is central to the multilateral system. The Universal Declaration of Human Rights (United Nations, 1948) stressed the importance of well-being and, implicitly, of improved quality of life, both of which are linked to the rights to social security, work, an adequate standard of living, education and health. The International Covenant on Economic, Social and Cultural Rights (United Nations, 1966) broadened this approach, with detailed specifications regarding social protection and the assistance to individuals and families that its implementation would require.