According to the 2010 Global Go To Think Tank Rankings released by the Think Tanks and Civil Societies Program at the International Relations Program, University of Pennsylvania, United States is the country with the largest number of think tanks in the world, followed by China and India.
The program created a process for ranking think tanks around the world, based on a worldwide survey of close to 1500 scholars, policy makers, journalists and regional and subject area experts.
All 6480 think tanks in the world were contacted and encouraged to participate in this nominations process.
Following is the list of the top 25 countries with the largest number of think tanks by the Think Tanks and Civil Societies Program:
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