| 2020health | United Kingdom | London | |
| Academy for the Development of a Democratic Environment (AZAD) | Malta | Valletta | 1976 |
| Academy of Liberalism | Estonia | Tallin | 2006 |
| Accion Emprendedora | Chile | Santiago de Chile | |
| Acton Institute | USA | Grand Rapids / Michigan | 1990 |
| Adam Smith Center | Poland | Warsaw | 1989 |
| Adam Smith Institute | UK | London | 1977 |
| Adam Smith Society | Italy | Mailand | |
| Adelphi Research | Germany | Berlin | 2001 |
| Adelphi consult | Germany | Berlin | 2002 |
| Adriatic Institute for Public Policy | Croatia | Rijeka | 2004 |
| AfroBarometer | International | | 1999 |
| Agenda Austria | Austria | Wien | 2013 |
| Aktionsgemeinschaft Soziale Marktwirtschaft | Germany | Tübingen | 1953 |
| Alaska Center for Public Policy | USA | Anchorage | 2004 |
| Albanian Liberal Institute | Albania | Tirana | |
| Alexander Langer Foundation | Italy | Bozen | 1999 |
| Allianz für den Rechtsstaat | Germany | Berlin | 1996 |
| Alois Mock Institut | Austria | St. Pölten | 2012 |
| Alternative Foundation | Spain | Barcelona | 2003 |
| American Economic Association | | | |
| American Enterprise Institute for Public Policy Research | USA | Washington, D.C. | 1938 |
| Americans for Tax Reform | | | |
| Amicus Europae Foundation | Poland | Warsaw | 2004 |
| Analytical Centre on Globalization and Regional Cooperation (ACGRC) | Armenia | Jerewan | |
| Anders Chydenius Foundation | Finland | Kokkola | |
| Andes Libres | Peru | Cusco | |
| Antall József Knowledge Centre | Hungary | Budapest | 2003 |
| Anton Tunega Foundation | Slovakia | Bratislava | 1992 |
| Arbejderbevaegelsens Erhvervsrad | Denmark | Copenhagen | 1936 |
| Arkansas Advocates for Children and Families | USA | Little Rock | 1977 |
| Asian Institute of Policy Studies | | | |
| Asociacion Escuela Cristiana de Liderazgo | Peru | Iquitos | 2011 |
| Asociacion Nacional de Fomento Economico | Costa Rica | San Jose | 1958 |
| Asociacion de Consumidores Libres | Costa Rica | San José | |
| Association Culturelle Joseph Jacquemotte | Belgium | Brussels | 1961 |
| Association for Liberal Thinking | Turkey | Ankara | |
| Association for Modern Economy | | | |
| Association for the Development of the Romanian Social Forum (AD FSR) | Romania | Bucharest | 2005 |
| Association of Private Enterprise Education | | | |
| Associazione Bruno Trentin - ISF - IREF | Italy | Rome | 2014 |
| Atlantic Commission (Netherlands) | | | |
| Atlantik-Brücke e.V. | Germany | Berlin | 1952 |
| Atlas Initiative für Recht und Freiheit e.V. | Germany | Frankfurt am Main | 2019 |
| Atlas Network | USA | | 1981 |
| Atvisa visuomene ir jos draugai | Lithuania | Klaipėda | 2005 |
| Austrian Economics Center | Austria | Vienna | 2006 |
| Austrian Institute for European Security Policy | Austria | Maria Enzersdorf | 1996 |
| Avenir Suisse | Switzerland | Zürich | |
| BEworks | Canada | Toronto | 2010 |
| BVA Group - Nudge et Comportement | France | Boulogne-Billancourt | |
| Behavioral Economics Group | UK | | 2008 |
| Behavioral Science and Policy Association | USA | Durham, NC | 2012 |
| Behavioral Science and Policy Center | USA | Durham, NC | 2012 |
| Behavioural Economics Team of the Australian Government | Australia | Canberra | 2016 |
| Behavioural Economics in Action at Rotman (BEAR) | Canada | Toronto, ON | |
| Behavioural Experiments in Health Network | UK/EU | London | 2015 |
| Behavioural Insights Team | UK/international | London | 2010 |
| Behavioural Scientist | USA | New York | 2017 |
| Belarusian Institute for Strategic Studies (BISS) | Lithuania;Belarus | Vilnius | |
| Berliner Institut für christliche Ethik und Politik | | | |
| Bertelsmann Foundation | Germany | Gütersloh | 1977 |
| Bertil Ohlin Institute | Sweden | Stockholm | 1993 |
| Bibliothek des Konservatismus | Germany | Berlin | 2012 |
| Blaue Narzisse | Germany | 09131 Chemnitz | 2004 |
| Bluegrass Institute for Public Policy Solutions | | | |
| Bow Group | | | |
| Brookings Institution | | | |
| Bund Deutscher Unitarier | Germany/EU | Giessen | 2009 |
| Bund der Steuerzahler e.V. | Germany | Berlin | 1949 |
| Bureau de Helling | Netherlands | Utrecht | 1990 |
| Burkestichting | Netherlands | Den Haag | |
| Business for New Europe | United Kingdom | London | |
| Bündnis Recht und Demokratie | Germany | Frankfurt am Main | |
| Bürgerkonvent | Germany | Berlin | 2003 |
| C02-Coalition | USA | | 2015 |
| CARIBBEAN POLICY RESEARCH INSTITUTE | Jamaica | | 2008 |
| CEDER Study Centre of CD&V | Belgium | Brussels | |
| CEE Network for Gender Issues | Slovenia | Ljubljana | 1998 |
| CEVRO Institute | | | |
| CEVRO Liberal Conservative Academy | Czech Republic | Prague | 1999 |
| CONTRIBUYENTES POR RESPETO | Peru | | |
| CREO | El Salvador | | |
| CREO (Centrum Rozwoju Edukacji Obywatelskiej) | Poland | Gdańsk | 2006 |
| California Budget Project | USA | Sacramento, CA | |
| Caminos de la Libertad | Mexico | México D.F. | 2005 |
| Canadian Institute for Advanced Research | Canada | Toronto, ON | 1982 |
| Capitol Research Center | | | |
| Captus | Sweden | Malmö | 2005 |
| Carl Friedrich von Siemens Stiftung | | | 1960 |
| Carnegie Trust UK | United Kingdom | Dunfermline | 1913 |
| Cassandra | | | |
| Catalanist and Democrat Foundation (CatDem) | Spain | Barcelona | 1994 |
| Cato Institute | USA | Washington | 1977 |
| Cato Institute en Español | | | 1998 |
| Causa Liberal | Portugal | Porto | |
| Center for Advanced Hindsight | USA | Durham, NC | 2007 |
| Center for Civic Education (CREO) | Poland | Gdansk | 2006 |
| Center for Democracy Foundation | Serbia | Beograd | 1994 |
| Center for Economic Development (CED) | Bulgaria | Sofia | |
| Center for Economic Development (CPHR) | Slovenia | Bratislava | |
| Center for Economics and Politics (CEP) | | | |
| Center for European Policy | Germany | Freiburg | 2006 |
| Center for European Policy Analysis | | | |
| Center for European Renewal | | | |
| Center for Financial Stability | USA | New York | 2009 |
| Center for Freedom and Prosperity | | | |
| Center for Institutional Analysis and Development | Romania | Bucharest | 2005 |
| Center for Liberal-Democratic Studies (CLDS) | Serbia | | |
| Center for Liberty Studies | Lithuania | | 2013 |
| Center for Social and Economic Research (CASE) | Poland | Warschau | |
| Center for Strategic and International Studies | | | |
| Center for the Rule of Law | | | |
| Center for the Study of Democracy (CSD) | Bulgaria | Sofia | |
| Center of Economic Research ETH Zürich | | Zürich | |
| Center on Global Prosperity of the Independent Institute | USA | | 1986 |
| Central Innovation Hub (at the Privy Council) | Canada | Ottawa, ON | 2015 |
| Centre Jean Gol | Belgium | Brussels | 2004 |
| Centre Party International Foundation | Sweden | Stockholm | 1995 |
| Centre d’Analyse Economique | | | |
| Centre for Analysis and Simulation of Air Operations | France | Lyon | |
| Centre for Analysis of Risk and Regulation (CARR) | UK | London | 2001 |
| Centre for Democracy and Development (Nigeria) | Nigeria | Abuja | 1997 |
| Centre for Development and Enterprise (South Africa) | South Africa | Johannesburg | 1995 |
| Centre for Economics and Politics (CEP) | Czech Republic | Prag | 1998 |
| Centre for Entrepreneurship and Economic Development (CEED) | | | |
| Centre for European Policy Studies | Belgium | Brussels | 1983 |
| Centre for European Reform (CER) | United Kingdom | | 1996 |
| Centre for European Studies | | | |
| Centre for Liberal Strategies (CLS) | Bulgaria | Sofia | |
| Centre for Medicine in the Public Interest | | | |
| Centre for Policy Alternatives | | | |
| Centre for Policy Studies (CPS) | United Kingdom | London | 1974 |
| Centre for Political Studies (CEPOS) | Denmark | Copenhagen | |
| Centre for Political Thought | Poland | Krakow | 1992 |
| Centre for Politics and Euro-Atlantic Partnership | | | |
| Centre for Research into Post-Communist Economies (CRCE) | United Kingdom | London | |
| Centre for Social and Economic Research (RSE) | Iceland | Reykjavík | |
| Centre for the New Europe | Belgium | Brussels | |
| Centre for the Study of Democracy and Culture | Czech Republic | Brno | 1993 |
| CentreForum | UK | London | 2005 |
| Centro Einaudi | Italy | Turin | |
| Centro Interdisciplinar de Etica e Economia Personalista | Brazil | Rio de Janeiro | 2002 |
| Centro Regional de Estrategias Economicas Sostenibles | Dominican Republic | Santo Domingo | 2009 |
| Centro Tocqueville Acton | Italy | Milan | 2007 |
| Centro de Analisis para Politicas Publicas | Dominican Republic | Santo Domingo, D.N. | |
| Centro de Divulgacion del Conocimiento Economico para la Libertad | Venezuela | Caracas | 1984 |
| Centro de Economia, Sociedad y Empresa (ESE) | Uruguay | Montevideo | |
| Centro de Estudios Economico-Sociales | Guatemala | Guatemala | 1959 |
| Centro de Estudios Equidad | Chile | Valparaíso | |
| Centro de Estudios Legales sobre el Terrorismo y sus Victimas | Argentina | Buenos Aires | |
| Centro de Estudios Libertad y Responsabilidad | Argentina | | |
| Centro de Estudios Publicos - Chile | Chile | Santiago de Chile | 1980 |
| Centro de Estudios de la Realidad Economica y Social | Uruguay | Montevideo | |
| Centro de Estudios para el Desarrollo | Uruguay | | |
| Centro de Implementacion de Politicas Publicas para la Equidad y el Crecimiento | Argentina | Buenos Aires | 2000 |
| Centro de Investigacion de Instituciones y Mercados de Argentina | Argentina | Buenos Aires | |
| Centro de Investigacion de Medios y Sociedad Andes | Chile | Santiago de Chile | |
| Centro de Investigacion para el Desarrollo, A. C. | Mexico | | 1984 |
| Centro de Investigacion y Estudios Legales | Peru | | 1989 |
| Centro de Investigaciones Economicas Nacionales | Guatemala | Guatemala | 1981 |
| Centro de Investigaciones sobre la libre empresa | Mexico | Mexico D.F. | |
| Centro del Liberalismo Clásico | | | |
| Centro para la Apertura y el Desarrollo de America Latina | Argentina | Buenos Aires | 2003 |
| Centro para la Apertura y el desarrollo de America Latina | Uruguay | Montevideo | |
| Centro para la Libertad y el Desarrollo | Peru | Virtual Organisation (no headquarter) | 2011 |
| Centro per la riforma dello stato | Italy | Rome | 1972 |
| Centrum Liberalnich Studii | Czech Republic | Prague | 1994 |
| Centrum Pieter Gillis | | | |
| Cercle Frédéric Bastiat | | | |
| Chatham House | | | |
| Chifley Research Center | Australia | Kingston, ACT | 2000 |
| Circulo de Empresarios | Spain | Madrid | 1977 |
| Ciudadano Austral | Chile | Castro | |
| Civic Institute | Czech Republic | Prag | |
| Civil Society Coalition on Climate Change | | | |
| Civil Society Institute (iFRAP) | France | Paris | 1981 |
| Civil-Military Cooperation | Netherlands | The Hague | |
| Civis | | | |
| Civismo | Spain | Pamplona | 2009 |
| Civita | Norway | Oslo | |
| Civitas | United Kingdom | London | 2000 |
| Clemson Institute for the Study of Capitalism | | | |
| Clexit | | | |
| Club 2015 | | | |
| Cobden Centre | | | |
| Cogito | Sweden | Stockholm | 1995 |
| Cold Weather Operations | Norway | Bodø | |
| Cologne Institute for Economic Research | Germany | Köln | 1951 |
| Combined Joint Operations from the Sea | USA | Norfolk | |
| Command and Control | Netherlands | Utrecht | |
| Committee For A Constructive Tomorrow | USA | Washington DC | 1985 |
| Compact | | Leipzip | 2010 |
| Competitive Enterprise Institute | | | 1984 |
| Competitive Malta | | | |
| Conservative Institute of M. R. Stefanik | Slovakia | Bratislava | 1999 |
| Conservative Technology Forum | | | |
| Constantine Karamanlis Institute for Democracy | Greece | Athens | 1998 |
| Contribuables Associés | | | |
| Cooperative Cyber Defence | Estonia | Tallinn | |
| Coordinadora por la Inversion y el Trabajo | Peru | Lima | 2004 |
| Corporacion Excelencia en la Justicia | Colombia | Bogotá | 1996 |
| Council for National Policy | | | |
| Council on Foreign Relations | | | |
| Council on Public Policy | Germany | Bayreuth | 2001 |
| Counter Intelligence | Poland | Krakow | |
| Counter-Improvised Explosive Devices | Spain | Madrid | |
| Crisis Management and Disaster Response | Bulgaria | Sofia | |
| Croatian Statehood Foundation (ZHDZ) | Croatia | Zagreb | 1995 |
| Cul:tra | Portugal | Lisbon | |
| Cultural Association Punto Rosso | Italy | Milan | 1991 |
| Círculo Acton Chile | Australia | | |
| Danish Nudging Network | Denmark | | 2010 |
| De Gasperi Foundation | Italy | Rome | 1982 |
| De Warande | | | |
| Defence Against Terrorism | Turkey | Ankara | |
| Degussa Sonne/Mond Goldhandel GmbH | Germany | Munich; Frankfurt | 2010 |
| Democracia & Desarrollo Internacional | Peru | Lima | 2008 |
| Democracy Lab- Costa Rica | Costa Rica | | |
| Democracy in Africa Research Unit (South Africa) | South Africa | Cape Town | 2002 |
| Democracía & Mercado | Chile | Santiago de Chile | 2009 |
| Democratic Civic Association (DCA) | Finland | Helsinki | 1986 |
| Demos (LT) | Lithuania | Vilnius | 2008 |
| Desiderius-Erasmus-Stiftung | Germany | Berlin | 2015 |
| Deutsche Bank Research | Germany | Frankfurt am Main | |
| Deutsche Gesellschaft für Auswärtige Politik (German Council on Foreign Affairs) | | | 1945 |
| Deutsches Institut für Urbanistik | | | |
| Deutsches Institut für Wirtschaftsforschung e.V. | | Berlin | |
| Deutschlandbewegung | Germany | Starnberg | |
| Die Familienunternehmer - ASU | Germany | Berlin | 1949 |
| Die Freie Welt | Germany/EU | 10119 Berlin | 2008 |
| Diktio Network | Greece | | 2013 |
| E.G. West Centre | United Kingdom | Newcastle | |
| E2T2 Hellenic Conservatives and Reformists' Think Tank | Greece | Glyfada | |
| ECIPE | Belgium | Brüssel | 2006 |
| ECONWATCH | Germany | Berlin | 2007 |
| EIKE | Germany | Jena | 2007 |
| EIPF | | | |
| ESEADE | Argentina | Buenos Aires | 1978 |
| Earhart Foundation | | | |
| EcoAustria | Austria | Wien | 2011 |
| Economic Freedom and Social Progress Association | | | |
| Economic Policy Institute | USA | Washington, D.C. | 1986 |
| Economic Policy Research Institute (EPRI) | | | |
| Economic and Social Research Center | Austria | Vienna | 2000 |
| Economic and Social Research Institute | Ireland | Dublin | 1960 |
| Economica Institut für Wirtschaftsforschung | | | |
| Ecopolis Foundation | Hungary | | 2010 |
| EdChoice | USA | Indianapolis | 1996 |
| Edmund Burke Institute | | | |