The JKW Foundation is a private foundation run by left-progressive commentator, and part-owner and former editor of the left-wing magazine The Nation Katrina vanden Heuvel and her sister, actress and film producer Wendy vanden Heuvel.  The organization mostly funds various performing arts projects, but also some left-of-center causes.
The JKW Foundation is the private foundation of the children of Jean Stein and Carter administration U.S. Ambassador to the European Office of the United Nations William vanden Heuvel, left-progressive commentator, and part-owner and former editor of the left-wing magazine The Nation Katrina vanden Heuvel and actress Wendy vanden Heuvel.  The JKW Foundation was incorporated as a charity in 1997 by their mother, Jean Stein.  Stein, a famous author and socialite, died from suicide in 2017. At the time of her death, Stein was worth $38.5 million and left the bulk of her fortune to her daughters and the JKW Foundation. 
In 2019, Saint Ignatius of Antioch Episcopal Church in New York City received support from the JKW Foundation to establish a music series to celebrate the life of Jean Stein.  In May 2019, the support culminated in memorial concert with various works by Baroque composer George Frideric Handel. 
The JKW Foundation financially supports SPACE on Ryder Farm, a nonprofit residency program and environmentalist-aligned farm in Putnam County, New York that caters to artists. SPACE supports left-progressive “social justice” and works to provide “artists and changemakers with time and space to create vital art and to foster necessary dialogue for lasting change.”  To encourage voter participation in the 2020 election, SPACE established a voter registration drive. 
In the past, the JKW Foundation has supported Human Rights Watch, an international non-governmental organization that conducts research and advocacy on human rights and which receives funding from various left-of-center foundations, including the Open Society Foundations. 
The JKW Foundation is listed as a supporter of the 52nd Street Project,  of which Wendy vanden Heuvel is a board member.  In 2009, money from the JKW foundation went towards a capital campaign to build a new clubhouse and theater for the organization. 
The JKW Foundation also supports a number of other preforming arts projects, including the Massachusetts Museum of Contemporary Art, Barrow Group Theatre Company,A.I.M. (Abraham in Motion), Earth Celebrations, Chicken and Egg Pictures, St. Ann’s Warehouse, Anonymous Ensemble, Film Forum, Working Theater, and Notch Theater.