The collection consists of sixteen boxes of papers, correspondence, memorabilia, newspaper clippings, and music for jazz ensembles of various sizes, as well as one piece of realia.

The collection consists primarily of photos, along with proofs for a plaque in honor of Leon Breeden, graphics for a plaque for Kenton Hall in the Music Building, Stan Kenton memorabilia, a large black-and-white poster of John F. Kennedy, a plaque in honor of J. Frank and Mary Lively from the UNT Jazz Studies division, a bust of Stan Kenton, and other ephemera.

The collection consists of materials generated by or related to the Jazz Studies program at the University of North Texas College of Music.

The collection consists of Leon Breeden's extensive, and often self-selected archival materials from his entire career, during which time the One O'Clock Lab Band and the UNT Jazz Studies program rose to international prominence. Also present are personal recordings and writing, compositions, memorabilia, photos, and materials from his time at Texas Christian University, in New York City, and at Grand Prairie High School.

The collection consists of one box of instantaneous sound discs of radio programs and live performances featuring the Moonmaids and the Swingtet (sometimes "Swingtette"), which was the forerunner to the Moonmaids at the University of North Texas. A few related performers (Page Cavanaugh Trio) are also present.

The collection consists of two boxes of photos, band parts, and saxophone method books from Robert L. Marquis, Jr., dating from his time with the Aces of Collegeland.