- Brookings
- Chatham House
- Carnegie Endowment for International Peace (CEIP)
- Center for Strategic and International Studies (CSIS)
- Bruegel
- Council on Foreign Relations (CFR)
- International Institute for Strategic Studies (IISS)
- RAND Corporation
- Wilson Center
- Amnesty International
- Cato Institute
- Heritage Foundation
- Fundacao Getulio Vargas (FGV)
- Transparency International (TI)
- Japan Institute of International Affairs (JIIA)
- French Institute of International Relations (IFRI)
- Fraser Institute
- German Institute for International and Security Affairs (SWP)
- Center for American Progress (CAP)
- Peterson Institute for International Economics (PIIE)
- Centre for European Policy Studies (CEPS)
- Stockholm International Peace Research Institute (SIPRI)
- Centre for Economic Policy Research (CEPR)
- Carnegie Moscow Russia
- Konrad Adenauer Foundation (KAS)
Here is Think Tank Watch's "cheat sheet" for the 2016 think tank rankings.