There are 5,465 think tanks worldwide.
- 1,872 in North America
- 1,208 in Western Europe
- 653 in Asia
- 538 in Latin America and the Caribbean
- 514 in Eastern Europe
- 424 in sub-Saharan Africa
- 218 in the Middle East and North Africa
- 38 in Oceania
- There are 1,777 think tanks in the United States.
- Nine out of 10 U.S. think tanks were created since 1951.
- The number of U.S. think tanks has more than doubled since 1980.
- Approximately 350 think tanks are based in Washington, more than in any country other than the United States.
To create a more manageable list from which to identify leading think tanks, an international group of scholars, think tank executives, public and private donors, and policymakers were then asked to nominate think tanks they consider to be the best in the world. These experts used selection criteria such as a think tank's ability to retain elite scholars and analysts; access to elites in policymaking, media, and academia; media reputation; reputation with policymakers; scholarly output; and usefulness of the organization's information, among others. This effort resulted in a list of approximately 400 think tanks worldwide that were then included in the Think Tank Impact Survey.
The Think Tank Impact Survey was then sent to hundreds of think tank scholars, think tank executives, and government and NGO personnel who fund think tanks. More than 150 responses from this panel of experts were received. These respondents ranked the list of think tanks by region and research area, the results of which are seen here.
James McGann is assistant director of the international relations program at the University of Pennsylvania and director of the Think Tanks and Civil Societies Program.