The Institute for Policy Studies (IPS) is an American progressive think tank, formed in 1963 and based in Washington, D.C. It was directed by John Cavanagh from 1998 to 2021. In 2021, Tope Folarin assumed the position of executive director. IPS focuses on US foreign policy, domestic policy, human rights, international economics, and national security.

IPS has been described as one of the five major independent think tanks in Washington during its first decades. Members of the IPS played key roles in the civil rights and anti-war movements of the 1960s, in the women's and environmental movements of the 1970s, and in the peace, anti-apartheid, and anti-intervention movements of the 1980s.

The IPS has come to be seen as an institutional outgrowth of the New Left movement of the 1960s and 1970s. In 1981, political scholar Joshua Muravchik wrote that its "genius" lay in how it acted "as a bridge between radicalism and the liberal establishment." According to Emory University historian Harvey Klehr, writing in 1988, the IPS served "as an intellectual nerve center for the radical movement." Two decades after its start, co-founder Marcus Raskin commented the IPS "had an extraordinary conceit. We were going to speak truth to power." A 2022 report by the Capital Research Center, "Institute for Policy Studies: The Left's Original Think Tank", stated that the IPS at present "probably doesn't make the shortlist of finalists for most influential left-of-center think tank in the country", compared to the Center for American Progress, the Center on Budget and Policy Priorities, or the Urban Institute, but "if one stretches the timeline back far enough", the IPS can be seen as a member of that group.

The IPS was founded in 1963 by Raskin and Richard Barnet as the think tank for "the most powerful of the powerless". The founders were officials in the John F. Kennedy administration – Raskin, then in his twenties, was working as a White House aide for McGeorge Bundy, and Barnet served in a similar role to John J. McCloy. They had become disillusioned by priorities based on politics rather than moral issues.

Against the backdrop of the counterculture of the 1960s, the opposition to US involvement in the Vietnam War, and the civil rights movement, the IPS "became a brand name for its unabashedly left-wing tone", in contrast with RAND and the largely conservative think tanks. Members of these movements came to IPS headquarters in Washington, D.C.'s Dupont Circle. In a 2009 interview, Raskin said, "Very quickly, with the Vietnam war, the civil rights movement, the women's movement, the institute became a place where different people from the movements came. People came in from demonstrations [and] camped out in the offices."

According to Raskin, "Early on [the IPS] had predicted that Vietnam would be a disaster." During the presidency of Lyndon Johnson, Raskin was indicted by the federal government for the 1965 publication of "tens of thousands of copies of an IPS anti-war Vietnam Reader"—a kind of textbook for anti-war teach-ins. He was charged with encouraging people to resist the draft. In 1967, Raskin and IPS Fellow Arthur Waskow penned "A Call to Resist Illegitimate Authority", a document signed by dozens of scholars and religious leaders which helped to launch the draft resistance movement.

In 1964, several leading black activists joined the institute's staff and made IPS into a base for supporting the civil rights movement. Fellow Bob Moses organized trainings for field organizers of the Student Nonviolent Coordinating Committee on the links between civil rights theory and practice, while Ivanhoe Donaldson initiated an assembly of black government officials. Co-writer of the Port Huron Statement at Students for a Democratic Society (SDS) and civil rights veteran, IPS Fellow Robb Burlage launched the critical health care justice movement in 1967 with his "Burlage Report". The next year, Burlage founded the Health Policy Advisory Center, which began publishing the Health/Pac Bulletin. The Bulletin's broad audience included "radicalized medical students and physicians and neighborhood activists" and "nervous health administrators at powerful medical centers pilloried in each issue"; it became a bimonthly until its closure in 1994.

The IPS was also at the forefront of the feminist movement. Fellow Charlotte Bunch organized a significant women's liberation conference in 1966 and later launched Quest: A Feminist Quarterly, a feminist journal. Rita Mae Brown wrote and published her notable lesbian coming-of-age novel, Rubyfruit Jungle, while on the staff in the 1970s.^{[citation needed]}