These US-based think tanks include both long-established institutions and newer, community-focused organizations. They offer research, policy analysis, and networking opportunities across various sectors. For example, the Council on Foreign Relations provides analysis on international issues, while the Center for Strategic and International Studies focuses on strategic insights and policy solutions. Chief is a private network for executive women, and Pavilion is a community for B2B tech go-to-market leaders. Many of these organizations are based in New York and Washington.
The companies listed show a mix of founding eras, with several established in the early to mid-20th century, such as the American Enterprise Institute (1938) and The Brookings Institution (1916). However, there is also a significant presence of younger organizations founded in the last few years, like Chief (2019) and RevGenius (2020), which often focus on professional networking and community building.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 | 7,729 | ||||
| 2 |
Pavilionjoinpavilion.com
Private community for B2B tech go-to-market leaders offering networking, learning, events, courses, and a curated knowledge hub. |
5,431 | |||
| 3 |
RevGeniusrevgenius.com
A community of revenue professionals collaborating on the future of B2B GTM through learning, sharing, and growing together |
3,740 | |||
| 4 |
Council on Foreign Relationscfr.org
An independent nonpartisan organization providing analysis on international issues through a think tank, publication of Foreign Affairs magazine, and online resources |
2,183 | |||
| 5 |
Center for Strategic and International Studies (CSIS)csis.org
A bipartisan, nonprofit policy research organization in Washington, DC, dedicated to providing strategic insights and policy solutions for a better world |
1,755 | |||
| 6 |
PreSales Collectivepresalescollective.com
The company aims to elevate the role of PreSales globally by providing resources, knowledge, networking, and mentorship for career development in PreSales |
1,202 | |||
| 7 |
German Marshall Fund of the United Statesgmfus.org
Nonpartisan organization promoting transatlantic partnership to address 21st-century challenges and opportunities between Europe and North America. |
975 | |||
| 8 |
American Enterprise Instituteaei.org
A public policy think tank dedicated to defending human dignity, expanding human potential, and promoting freedom and opportunity worldwide |
967 | |||
| 9 |
The Conference Boardconference-board.org
Provides trusted, non-partisan economic and business insights through research and analysis for members and the public. |
911 | |||
| 10 |
The Brookings Institutionbrookings.edu
A renowned think tank conducting independent research, offering innovative policy solutions, and consistently ranked as the most influential and trusted globally |
907 | |||
| 11 |
The Heritage Foundationheritage.org
A conservative think tank founded in 1973, focused on promoting free enterprise, limited government, individual freedom, traditional values, and a strong national defense |
805 | |||
| 12 |
Milken Institutemilkeninstitute.org
A nonprofit think tank promoting diversity and inclusion, providing resources, training, and opportunities for personal and professional growth in various office locations |
775 | |||
| 13 |
Hoover Institution, Stanford Universityhoover.org
Researching economics, politics, and international affairs to advance ideas promoting economic opportunity, prosperity, and securing peace for America and humanity. |
652 | |||
| 14 |
The Postthepost.co
A private membership network founded by elite athletes, providing access to a network, exclusive experiences, coaching, and a clubhouse for leaders in sport |
530 | |||
| 15 |
Hamptonjoinhampton.com
Provides a highly vetted membership community for entrepreneurs, founders, and CEOs to connect, share knowledge, and grow their businesses. |
529 | |||
| 16 |
The Old Girls Clubjointheogc.com
Connects ambitious women and non-binary individuals for tactical support, sharing insights, guidance, and resources on careers, compensation, family planning, and leadership strategies. |
526 | |||
| 17 |
CREWcrewexec.com
A transformative membership network offering leadership development through self-awareness, networking, learning, coaching, events, and connections with top commercial leaders |
452 | |||
| 18 |
Carnegie Endowment for International Peacecarnegieendowment.org
A global think tank dedicated to advancing international cooperation and engagement, with offices in key world capitals and a nonpartisan focus on practical results |
386 | |||
| 19 |
New Americanewamerica.org
A civic platform generating big ideas, designing evidence-based policies, and sharing solutions to public problems through partnerships and storytelling |
366 | |||
| 20 |
Cato Institutecato.org
Promoting American public policy centered on individual liberty, limited government, free markets, and peaceful international relations |
338 | |||
| 21 |
Modern Sales Prosmodernsaleshq.com
An exclusive peer learning community for sales professionals, focused on sales leadership, management, operations, and enablement, offering high-quality education and resources |
332 | |||
| 22 |
Center for American Progressamericanprogress.org
independent nonpartisan policy institute promoting bold progressive ideas, leadership, and action to improve lives of all Americans |
325 | |||
| 23 |
GRI Institutegriinstitute.org
A London-based ecosystem connecting real estate and infrastructure decision makers, providing exclusive networking opportunities and valuable market insights since 1998 |
314 | |||
Want more companies than this list?This page shows the largest ones only. Connect to Tamtam to see every company that matches, filter by size, industry or growth, and reach their decision-makers. | |||||
| 24 |
Foundation for Defense of Democracies (FDD)fdd.org
A non-partisan policy institute in Washington, DC focusing on foreign policy and national security |
273 | |||
| 25 |
Hudson Institutehudson.org
Non-partisan policy research organization focused on global security, prosperity, and freedom Offers interdisciplinary studies, publications, conferences, and strategic recommendations to government and business leaders |
254 | |||
| 26 |
SDR Leaders of USAsdrleaders.global
This community helps Sales Development leaders in the USA network and learn from each other, sharing best practices to help members grow and improve. |
194 | |||
| 27 |
Homeschoolingoptoutshow.com
The company advocates for homeschooling, pursuing passions, respecting family, critical thinking, physical activity, social skills, moral discussions, uniqueness, and love and respect |
180 | |||
| 28 |
Manhattan Institutemanhattan.institute
A group of scholars, journalists, activists, and leaders working to promote opportunity, individual liberty, and the rule of law in America's cities |
180 | |||
| 29 |
Rice University's Baker Institute for Public Policybakerinstitute.org
A nonpartisan think tank based at Rice University focused on bridging theory and practice of public policy through expert collaboration |
178 | |||
| 30 |
Bipartisan Policy Centerbipartisanpolicy.org
The company fosters bipartisan relationships to promote health, security, and civic participation, providing support and policy insights for effective legislative action |
177 | |||
| 31 |
Lincoln Institute of Land Policylincolninst.edu
Nonprofit foundation researching and recommending innovative land solutions to address economic, social, and environmental challenges, informing global public policy decisions through education and events |
172 | |||
| 32 |
Lifeboat Foundationlifeboat.com
Nonprofit organization encouraging scientific advancements, protecting humanity from existential risks, and potential misuse of powerful technologies like genetic engineering, nanotechnology, and robotics/AI. |
170 | |||
| 33 |
Suprajoinsupra.com
An exclusive network for Product leaders to connect with peers, make better decisions, and achieve exponential career growth through curated groups |
169 | |||
| 34 |
AI Circleai-circle.org
Community of founders and operators developing and deploying models that advance the frontier of AI, hosting events globally. |
168 | |||
| 35 |
Third Waythirdway.org
A national think tank advocating modern center-left ideas focused on opportunity, freedom, and security through impactful advocacy campaigns and rigorous policy research |
165 | |||
| 36 |
Gain Grow Retaingaingrowretain.com
An open community for B2B SaaS Customer Success leaders offering actionable support, best practice discussions, and content through multiple platforms |
161 | |||
| 37 |
Ximusximusforum.com
Closed community of exceptional Israeli business leaders for professional, personal, and social growth through invitation-only events and discussions. |
159 | |||
| 38 |
FutureWomenXfuturewomenx.com
Elevating women to be future-makers and powering our collective future by unleashing their limitless potential and power, creating a more gender-equal world. |
158 | |||
| 39 |
3i Members3imembers.com
An exclusive community connecting private investors to unique alternative investment opportunities, fostering discussions and sharing insights in emerging sectors |
157 | |||
| 40 |
Harvard's Belfer Centerbelfercenter.org
The organization at the hub of Harvard Kennedy School focuses on research and leadership in international security, diplomacy, and environmental issues |
154 | |||
| 41 | 
New Prospects Collaborativedhs.gov
The company provides support to law enforcement agencies at all levels to ensure safe and crime-free communities globally |
151 | |||
| 42 |
Capitacapita.org
An independent think tank focused on global issues, working to ensure all children and families thrive and strengthen social fabric |
149 | |||
| 43 |
Startup Virginiastartupvirginia.org
A nonprofit high-growth business incubator and entrepreneurial hub providing support, mentorship, education, and workspace to startup companies and entrepreneurs |
35 | |||
| 44 |
Asset Leadership Networkassetleadership.net
Industry organization focused on impacting asset management in various sectors, promoting ISO 55000 compliance for optimal asset value, performance, and risk management |
14 | |||
| 45 |
Club Praxisclubpraxis.com
Specialized French American think tank focusing on Government Open Data and Public Policy Performance measurement through various key projects and conferences |
2 | |||
| 46 |
fyl铆fylitribe.com
A female mastermind membership community empowering early stage female founders through education, mentorship, leadership advancement, and funding opportunities globally |
2 | |||
Turn this list into pipeline
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How this list is built
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 Nov 14, 2026.
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