The 61 largest International Affairs companies in the United States (2026 list)

#	Company	Industry	Headquarters	Employees	Founded
1	United Nations un.org An international organization committed to maintaining peace, tackling global challenges, providing humanitarian aid, promoting human rights, and advancing development worldwide	International Affairs	🇺🇸 New York	66,883	1945
2	U.S. Department of State state.gov The organization is dedicated to diplomacy, managing relationships with foreign governments, promoting America's interests, and representing citizens worldwide through diplomats and professionals	International Affairs	🇺🇸 Washington	37,601	n/a
3	UNDP undp.org Support countries in policy development, leadership, partnerships, and institutional capacity to eradicate poverty and reduce inequalities worldwide.	International Affairs	🇺🇸 New York	26,722	n/a
4	USAID usaid.gov This organization works to end global poverty and support resilient, democratic societies by promoting economic prosperity, democracy, health, education, and humanitarian assistance worldwide	International Affairs	🇺🇸 Washington	16,196	1961
5	United Nations Population Fund (UNFPA)unfpa.org Aims to ensure wanted pregnancies, safe childbirth, and empowerment of young people worldwide through sexual and reproductive health programs and initiatives	International Affairs	🇺🇸 New York	8,306	1969
6	Peace Corps peacecorps.gov An international service organization sending Americans abroad to work with communities in education, health, economic development, agriculture, environment, and youth development	International Affairs	🇺🇸 Washington	8,068	1961
7	UN Women unwomen.org An organization dedicated to gender equality and women's empowerment, working with governments and civil society to advance women's rights worldwide	International Affairs	🇺🇸 New York	4,805	2010
8	PATH path.org Global nonprofit dedicated to health equity, developing and scaling up innovative solutions to pressing health challenges through partnerships and expertise	International Affairs	🇺🇸 Seattle	3,515	1977
9	United Nations OCHA unocha.org Global emergency response coordination advocating for effective and principled humanitarian action to save lives and protect people in crises	International Affairs	🇺🇸 New York	1,917	1991
10	Veterans Affairs Hospital va.gov An international company based in Washington, DC that specializes in veterans affairs and healthcare services	International Affairs	🇺🇸 Washington	1,699	n/a
11	Pan American Health Organization paho.org An international public health agency founded in 1902, providing technical cooperation to improve health and quality of life in the Americas	International Affairs	🇺🇸 Washington	1,680	1902
12	Central Intelligence Agency linkedin.com Providing global intelligence through data analysis, covert operations, and cybersecurity to protect national security and preempt threats.	International Affairs	🇺🇸	1,575	n/a
13	Organización de los Estados Americanos oas.org Brings together 35 independent American states as a political forum focusing on democracy, human rights, security, and sustainable development.	International Affairs	🇺🇸 Washington	1,511	1948
14	The Fulbright Program fulbrightprogram.org Connecting passionate and accomplished students, scholars, and professionals globally through a network offering career development, grant opportunities, and community engagement	International Affairs	🇺🇸 Washington	1,434	1946
15	National Democratic Institute (NDI)ndi.org Nonprofit organization supporting democratic institutions globally through citizen participation, government accountability, and sharing best practices in international democratic development	International Affairs	🇺🇸 Washington	1,094	1983
16	Atlantic Council atlanticcouncil.org Educates, galvanizes, and promotes constructive leadership in international affairs, shaping policy choices and fostering strategies for global security and economic prosperity through various programs.	International Affairs	🇺🇸 Washington	1,039	1961
17	Ipas ipas.org This company advocates for reproductive justice by expanding access to abortion and contraception through a comprehensive approach worldwide	International Affairs	🇺🇸 Chapel Hill	960	1973
18	International Model United Nations Association (IMUNA)imuna.org This organization promotes global education through Model UN conferences, teaching students communication, decision-making, and negotiation skills	International Affairs	🇺🇸 New York	840	1975
19	Johns Hopkins School of Advanced International Studies (SAIS)sais.jhu.edu Training future cross-sector leaders to understand and navigate a turbulent world, shaping it for the better through cultural fluency and informed decision-making	International Affairs	🇺🇸 Washington	719	1943
20	Alight wearealight.org The company builds meaningful lives for displaced individuals by addressing basic needs and fostering joy, dignity, connection, and purpose globally	International Affairs	🇺🇸 Minneapolis	689	1978
21	United Nations Peacekeeping peacekeeping.un.org Provides peacekeeping services to assist countries in transitioning from conflict to peace by deploying troops, police, and civilian peacekeepers globally	International Affairs	🇺🇸 New York	636	1948
22	Iran Human Rights Documentation Center iranhrdc.org This organization documents human rights abuses in Iran since 1979, establishes responsibility, promotes accountability, and encourages dialogue on human rights	International Affairs	🇺🇸 New Haven	615	2005
23	SDSN Youth sdsnyouth.org A global network of young leaders working towards the Sustainable Development Goals through education advocacy, sustainable initiatives, and entrepreneurship	International Affairs	🇺🇸 New York	580	2015
24	United Nations Capital Development Fund (UNCDF)uncdf.org Mobilizes capital for impactful investments in high-risk markets, especially Least Developed Countries, contributing to job creation and economic growth.	International Affairs	🇺🇸 New York	563	1966
25	Kuwait Embassy A government agency involved in various governmental activities and services for the public	International Affairs	🇺🇸 Washington	563	n/a
26	Asia Society asiasociety.org An organization focused on understanding Asia's global role, hosting events, producing research, and bringing together experts in policy, business, arts, education, and culture	International Affairs	🇺🇸 New York	526	1956
27	Keller Wiliams yourkwoffice.com Providing services to the Philadelphia Main Line and nearby areas	International Affairs	🇺🇸 Bryn Mawr	501	n/a
28	Eurasia Group eurasiagroup.net Provides expert political risk research and consulting to help clients make informed business decisions in complex international political environments.	International Affairs	🇺🇸 New York	499	1998
29	U.S. Department of State - Bureau of Human Resources state.gov A leading training provider for US government foreign affairs personnel, offering courses in language, professional studies, technology, leadership, and management	International Affairs	🇺🇸 Washington	481	1947
30	Harvard Project for Asian and International Relations (HPAIR)hpair.org Organizes annual student conferences in the Asia-Pacific region, bringing together international students and leaders to discuss global issues and trends	International Affairs	🇺🇸 Cambridge	474	1991
31	Concordia concordia.net A nonprofit organization facilitating public-private partnerships to address global challenges through events and collaborations, promoting inclusivity and social impact	International Affairs	🇺🇸 New York	467	2011
32	United Nations Foundation unfoundation.org Independent charitable organization fostering partnerships and innovations to support the United Nations in addressing humanity’s greatest global challenges.	International Affairs	🇺🇸 Washington	463	1998
33	International Republican Institute iri.org The organization advances freedom and democracy worldwide by developing political parties, civic institutions, open elections, good governance, and the rule of law	International Affairs	🇺🇸 Washington	449	1983
34	The International Foundation for Electoral Systems ifes.org Promoting free and fair elections worldwide, strengthening electoral systems, empowering underrepresented groups, and advancing good governance through technical assistance and research	International Affairs	🇺🇸 Washington	421	1987
35	United Nations Global Compact unglobalcompact.org Global initiative aligning companies with principles on human rights, labor, environment, and anti-corruption to drive sustainable development goals worldwide	International Affairs	🇺🇸 New York	421	2000
36	Georgetown University Walsh School of Foreign Service sfs.georgetown.edu Premier school of international affairs founded in 1919, offering education grounded in theory, practice, and Jesuit values across two campuses	International Affairs	🇺🇸 Washington	404	1919
37	Middle East Institute mei.edu A Washington, DC-based institution founded in 1946 dedicated to studying the Middle East, increasing knowledge, and fostering better understanding between regions	International Affairs	🇺🇸 Washington	397	1946
38	American Refugee Committee wearealight.org A global organization providing lifesaving services and breakthrough solutions for displaced people, focused on unleashing abundance and designing human-worthy services	International Affairs	🇺🇸 Minneapolis	387	1979
39	Culmen International culmen.com Global provider of technical, management, humanitarian assistance, and logistics services with extensive experience operating in over 140 countries on six continents	International Affairs	🇺🇸 Alexandria	384	2004
40	United States Institute of Peace usip.org A national organization dedicated to promoting peace by working with local partners to prevent, mitigate, and resolve violent conflicts worldwide	International Affairs	🇺🇸 Washington	350	1984
41	Universal Peace Federation upf.org An international interreligious network promoting world peace through collaboration with representatives from various sectors and support for UN initiatives	International Affairs	🇺🇸 New York	345	2005
42	Pan American Development Foundation padf.org A nonprofit organization working in Latin America and the Caribbean to promote development and create opportunities for vulnerable communities	International Affairs	🇺🇸 Washington	336	1962
43	Embassy of France in the United States linktr.ee Representation of the French government in the United States through the French Embassy in Washington, DC and 10 Consulates General across the country	International Affairs	🇺🇸 Washington	290	1778
44	Human Rights Foundation (HRF)hrf.org A nonpartisan nonprofit organization promoting global human rights, focusing on closed societies, advocating for freedoms such as speech, association, and self-determination	International Affairs	🇺🇸 New York	251	2005
45	Embassy Of Lebanon lebanonembassyus.org An International Affairs company located in Washington, United States, focusing on representing Lebanon and promoting diplomatic relations globally	International Affairs	🇺🇸 Washington	227	n/a
46	Vital Voices Global Partnership vitalvoices.org Empowering women leaders worldwide through tailored investments and programs focused on leadership development, economic empowerment, and human rights advocacy	International Affairs	🇺🇸 Washington	193	1997
47	Major Group for Children and Youth unmgcy.org A self-organized space for children and youth to engage in UN policy processes, promoting their meaningful participation in sustainable development	International Affairs	🇺🇸 New York	187	1992
48	Mandela Washington Fellowship mandelawashingtonfellowship.org Empowering young African leaders through academic coursework, leadership training, and collaboration to drive economic growth, strengthen governance, and enhance peace	International Affairs	🇺🇸 Washington	185	2014
49	UN Sustainable Development Group unsdg.un.org An organization comprising 40 UN entities working in 165+ countries towards sustainable development goals and global progress	International Affairs	🇺🇸 New York	181	2019
50	Test University gmail.org This company offers unparalleled services and products	International Affairs	🇺🇸 Sunnyvale	164	2020
51	PNUD en América Latina y el Caribe undp.org The company partners with individuals worldwide to build nations resilient to crises, fostering sustainable growth and improved quality of life	International Affairs	🇺🇸 New York	164	1965
52	UNDP in Asia and the Pacific undp.org The company focuses on addressing diverse development challenges in Asia and the Pacific by promoting inclusive, pro-poor growth and sustainable development initiatives	International Affairs	🇺🇸 New York	155	1965
53	SkyLIFE skylifeglobal.com Revolutionizing supply chain delivery with aerial technology, specializing in military and humanitarian aid through customized, safe, and reliable aerodynamic packs and communication devices	International Affairs	🇺🇸 Maumee	154	2010
54	Accountability Lab accountabilitylab.org The company works to promote accountability, integrity, and positive social change by supporting change-makers and responsible leaders worldwide	International Affairs	🇺🇸 Washington	152	2012
55	Resolution Project resolutionproject.org A global nonprofit empowering young leaders in social entrepreneurship through programs like Social Venture Challenges and Resolution Fellowships	International Affairs	🇺🇸 New York	152	2007
56	Peace Winds peacewindsamerica.org Disaster preparedness organization advocating for collaboration between governments, militaries, NGOs, and private sector for global humanitarian assistance, emphasizing Japan - US relationship	International Affairs	🇺🇸 Washington	151	1996
57	YPFP (Young Professionals in Foreign Policy)ypfp.org Building nonpartisan leaders in foreign policy through events and dialogue between future leaders and experts across international branches	International Affairs	🇺🇸 Washington	151	2004
58	B20 USA uschamber.com Global business forum facilitating dialogue between G20 leaders and multinational corporations, with over 1,000 delegates representing 65 million businesses	International Affairs	🇺🇸 Washington	150	2008
59	European Union Delegation to the United States eeas.europa.eu A diplomatic mission representing the European Union in the United States, promoting EU policies to the US government and raising awareness of EU issues	International Affairs	🇺🇸 Washington	121	1950
60	Karfi karfi.org Connecting African social entrepreneurs with resources and support to effectively achieve UN's SDGs through consulting services and networking opportunities	International Affairs	🇺🇸 New York	7	2017
61	Graduate Programs in International Affairs at The New School newschool.edu Specializing in International Affairs programs, the company offers top-ranked IA programs, UN Summer Study, and International Field Programs	International Affairs	🇺🇸 New York	4	2001

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Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Oct 10, 2026.

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International Affairs companies in Washington 28