The A.J. Muste Memorial Institute is a grantmaking and sponsorship organization that supports left-wing activist groups, both in the United States and internationally. Founded by members of the War Resisters League, it is named for Abraham Johannes Muste, an early 20th century pacifist, labor organizer, and civil rights activist.
The Muste Institute retains close ties to the War Resisters League, providing the group with $66,255 in its 2017 fiscal year. 
The A.J. Muste Memorial Institute is a New York-based left-wing grantmaking organization that funds various anti-war causes around the world. The organization also provides affordable space for start-up peace groups to operate out of in New York City.
Members of the War Resisters League founded the A.J. Muste Memorial Institute “to offer safe space to radical organizations threatened by government surveillance and harassment.” Its organizing occurred during the movement against the U.S. involvement in the Vietnam War. The institute gained tax-exempt status in 1974. 
Its goals include ending war, exposing the “military industrial complex,” opposing nuclear power, seeking a “halt to environmental racism,” stopping the death penalty, reducing or ending incarceration, defending labor unions, promoting immigration, and fighting for racial and sexual equality. 
The group sets up grants to various left-wing and far-left organizations that advocate non-violence. The grants are divided along multiple categories.
The Social Justice grants targets helping groups around the U.S. and the world that have small budgets and little access to mainstream funding avenues.  The International Nonviolence Training Fund provides up to $4,000 to projects outside the United States.  The institute further sponsors “Collaborative Workspace” for what it calls “activist tenants” to conduct meetings, training, events and organizing projects. 
The Muste Institute also serves as a “Fiscal Sponsor” to various projects, helping groups get tax-deductible contributions. This assistance is aimed at smaller groups lacking the time, staff and financial resources to maintain a tax-exempt status. 
The organization publishes the activist newsletter Muste Notes, and also publishes a pamphlet series of historical and contemporary essays about social change. The organization counts among its grantees named on its website are Chiapas to Palestine, an Uruguayan human rights activist, the Parole Preparation Project, the War Resisters League, and Code Pink. 
The organization is named for Abraham Johannes Muste, an early 20th century pacifist, labor organizer, and civil rights activist. The organization says that Muste introduced Martin Luther King Jr. to the notion of nonviolent activism when King was a seminarian, although the organization says Muste and King had a “pretty heated argument” before King agreed. Further, the Muste Institute claims, it was A.J. Muste that introduced King to non-violent protest rather than Gandhi. 
A.J. Muste was born in 1885 in Holland, brought to the United States at the age of six, and raised by a Republican family. He became a Dutch Reformed minister. He voted for socialist Eugene Debs in the 1912 presidential election. Then, he switched to the more liberal Congregational Church and became a pacifist over World War I. In the 1920s, he became the director of the Brookwood Labor College in Katonah, New. York.
He helped found the Conference for Progressive Labor Action 1929, which helped form he American Workers Party in 1933. He eventually got so wrapped up in politics that he dropped his Christian pacifism to become an “avowed Marxist-Leninist,” according to the organization’s website. He was even involved in founding the Trotskyist Workers Party of America. However, after he met with Trotsky in Norway, he returned to the United States abandoning Marxist-Leninism and declaring his allegiance to Christianity again. 
In 1940, he became executive secretary of the religious pacifists’ organization, and held the post until 1953. He opposed U.S. intervention in World War II. In 1966, he led a group of pacifists to Vietnam to Saigon, who were arrested and threatened with deportation. Later that same year, he traveled to Hanoi and visited with Communist leader Ho Chi Minh. He died in 1967, while the Vietnam War continued. 
Heidi Boghosian is the executive director of the Muste Institute. She joined the staff in August 2014. She is a former executive director of the National Lawyers Guild and is the co-host of a radio show, Law and Disorder. She is also the author of the 2013 book Spying on Democracy: Government Surveillance, Corporate Power, and Public Resistance. 
Peter Muste is the grandson of A.J. Muste, and is a board member of the institute. 
The A.J. Muste Memorial Institute purchased a three-story, 9,789 square foot building in Manhattan in 1978 from the War Resisters League. The building became known as the “Peace Pentagon” and was used by far-left activist groups including Socialist Party USA, Occupy Wall Street and Granny Peace Brigade. The organization sold the building for $20.75 million in 2016. 
After the sale of the old “Peace Pentagon,” the Muste Institute bought a Brooklyn townhouse for $7.75 million.