Here’s a comprehensive list of major international organizations and their headquarters:

1. Arab League
   • Headquarters: Cairo
2. Amnesty International
   • Headquarters: London
3. United Nations Industrial Development Organization (UNIDO)
   • Headquarters: Vienna
4. Organization of the Petroleum Exporting Countries (OPEC)
   • Headquarters: Vienna
5. International Atomic Energy Agency (IAEA)
   • Headquarters: Vienna
6. Food and Agriculture Organization of the United Nations (FAO)
   • Headquarters: Rome
7. South Asian Association for Regional Cooperation (SAARC)
   • Headquarters: Kathmandu
8. European Parliament
   • Headquarters: Strasbourg
9. United Nations Children’s Fund (UNICEF)
   • Headquarters: New York
10. International Court of Justice (ICJ)
    • Headquarters: The Hague (Peace Palace in The Hague)
11. Economic and Social Commission for Asia and the Pacific (ESCAP)
    • Headquarters: Bangkok
12. Asia-Pacific Economic Cooperation (APEC)
    • Headquarters: Manila
13. Interpol
    • Headquarters: Lyon
14. Commonwealth Heads of Government Meeting (CHOGM)
    • Headquarters: London
15. Asian Development Bank (ADB)
    • Headquarters: Manila
16. European Commission
    • Headquarters: Brussels
17. Economic Commission for Western Asia (ECWA)
    • Headquarters: Baghdad
18. Economic and Social Commission for Asia and the Pacific (ESCAP)
    • Headquarters: Bangkok
19. United Nations (UN)
    • Headquarters: New York City (New York, USA)
20. United Nations
    • Headquarters: New York
21. United Nations International Children’s Emergency Fund (UNICEF)
    • Headquarters: New York City
22. World Trade Organization (WTO)
    • Headquarters: Geneva
23. World Health Organization (WHO)
    • Headquarters: Geneva
24. General Agreement on Tariffs and Trade (GATT)
    • Headquarters: Geneva
25. European Common Market (ECM)
    • Headquarters: Brussels, Belgium and Luxembourg
26. European Free Trade Association (EFTA)
    • Headquarters: Geneva
27. European Economic Community (EEC)
    • Headquarters: Brussels
28. International Labour Organization (ILO)
    • Headquarters: Geneva
29. Red Cross
    • Headquarters: Geneva
30. United Nations High Commissioner for Refugees (UNHCR)
    • Headquarters: Geneva
31. World Wildlife Fund (WWF)
    • Headquarters: Gland
32. North Atlantic Treaty Organization (NATO)
    • Headquarters: Brussels
33. Indian Ocean Commission
    • Headquarters: Mauritius
34. Commonwealth
    • Headquarters: London
35. World Bank
    • Headquarters: Washington, DC

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