Mutual Musicians Foundation is a National Historic Landmark in Kansas City, Missouri.
Since 1930, musicians have gathered at the foundation Friday and Saturday nights after midnight to jam into the early morning hours.
The foundation also serves as a rehearsal space for members, a classroom for visiting students, and a venue for private parties.
In 1979, the Mutual Musicians' Foundation Building was added to the National Register of Historic Places.
The Missouri House of Representatives passed "a provision to let the Mutual Musicians Foundation in Kansas City serve alcohol until 6 a.m." in May 2007.