The Hoover Institution is an American public policy think tank which promotes personal and economic liberty, free enterprise, and limited government. While the institution is formally a unit of Stanford University, it maintains an independent board of overseers and relies on its own income and donations. It is widely described as conservative, although its directors have contested the idea that it is partisan.

A think tank, or policy institute, is a research institute that performs research and advocacy concerning topics such as social policy, political strategy, economics, military, technology, and culture. Most think tanks are non-governmental organizations, but some are semi-autonomous agencies within government, and some are associated with particular political parties, businesses or the military. Think tanks are often funded by individual donations, with many also accepting government grants.