It is an international program with the following member states/countries and the year that they joined:
"1957: Afghanistan, Albania, Argentina, Australia, Austria, Belarus, Brazil, Bulgaria, Canada, Cuba, Denmark, Dominican Republic, Egypt, El Salvador, Ethiopia, France, Germany, Greece, Guatemala, Haiti, Holy See, Hungary, Iceland, India, Indonesia, Israel, Italy, Japan, Republic of Korea, Monaco, Morocco, Myanmar, Netherlands, New Zealand, Norway, Pakistan, Paraguay, Peru, Poland, Portugal, Romania, Russian Federation, Socialist Federal Rep. of Yugoslavia, South Africa, Spain, Sri Lanka, Sweden, Switzerland, Thailand, Tunisia, Turkey, Ukraine, United Kingdom, United States, Venezuela, Viet Nam
- 1958: Belgium, Ecuador, Finland, Iran, Luxembourg, Mexico, Philippines, Sudan
- 1959: Iraq
- 1960: Chile, Colombia, Ghana, Senegal
- 1961: Lebanon, Mali, Democratic Republic of the Congo
- 1962: Liberia, Saudi Arabia
- 1963: Algeria, Bolivia, Côte d'Ivoire, Libya, Syria, Uruguay
- 1964: Cameroon, Gabon, Kuwait, Nigeria
- 1965: Costa Rica, Cyprus, Jamaica, Kenya, Madagascar
- 1966: Jordan, Panama
- 1967: Sierra Leone, Singapore, Uganda
- 1968: Liechtenstein
- 1969: Malaysia, Niger, Zambia
- 1970: Ireland
- 1972: Bangladesh
- 1973: Mongolia
- 1974: Mauritius
- 1976: Qatar, United Arab Emirates, Tanzania
- 1977: Nicaragua
- 1983: Namibia
- 1984: China
- 1986: Zimbabwe
- 1992: Estonia, Slovenia
- 1993: Armenia, Croatia, Czech Republic, Lithuania, Slovakia
- 1994: The former Yugoslav Republic of Macedonia, Kazakhstan, Marshall Islands, Uzbekistan, Yemen
- 1995: Bosnia and Herzegovina
- 1996: Georgia
- 1997: Latvia, Malta, Moldova
- 1998: Burkina Faso
- 1999: Angola, Benin
- 2000: Tajikistan
- 2001: Azerbaijan, Central African Republic, Serbia
- 2002: Eritrea, Botswana
- 2003: Honduras, Seychelles, Kyrgyzstan
- 2004: Mauritania
- 2005: Chad
- 2006: Belize, Malawi, Montenegro, Mozambique
- 2007: Cabo Verde*
- 2008: Nepal, Palau
- 2009: Bahrain, Burundi, Cambodia, Congo, Lesotho, Oman
- 2011: Lao People's Democratic Republic, Tonga*
- 2012: Dominica, Fiji, Papua New Guinea, Rwanda, Togo, Trinidad and Tobago
- 2013: San Marino, Swaziland
- 2014: Bahamas, Brunei Darussalam, Comoros*
- 2015: Djibouti, Guyana, Vanuatu, Antigua and Barbuda, Barbados
- 2016: Saint Lucia*, Saint Vincent and the Grenadines*, The Gambia*, Turkmenistan"
Events on the calendar are located in a number of different countries from the above list. The headquarters is in Vienna, Austria.