Series I: General, 1806-2011 consists of subject files concerning to Dr. Moloney's professional life as a performer, promoter, producer, and fieldworker. Materials include newsletters produced by various Irish-American "Celtic" Societies; scholarly journals on music and ethnicity; photocopies of early 20th century Irish-American newspapers; business and personal correspondence; an extensive collection (referred to as "Bookings") of contracts and correspondence detailing Dr. Moloney's performance engagements; files documenting behind-the-scenes studio work ("Recording Projects"); financial records and ephemera pertaining to major and independent labels, such as Green Linnet, Shanachie, Topic, and Transatlantic, with emphasis on marketing and the business models applied to Irish music starting in the 1970s. Of particular note is a complete run of the Shanachie label's newsletter and a collection of record catalogs dating back to the 1920s.

The series also contains materials concerning Dr. Moloney's involvement in numerous federally funded projects, including the Smithsonian Institution Festival of American Folklife (1976), the Chicago Ethnic Arts Project (1977), the Green Fields of America ensemble, the 1982 Knoxville's World's Fair, the International Village Fair in Philadelphia (1987), the Philadelphia Ceili Group Festival, and the Irish Week at the Augusta Heritage Center in Elkins, West Virginia. Other projects are also documented, such as the development for the proposed multi-part series for Radio Telefis Eireann called The Green Fields of America and Emigrants and Exiles.

Series II: Individuals, 1879-2010 consists of materials collected by Dr. Moloney throughout the course of his academic and professional activities concerning specific individuals and groups. The majority of these individuals and groups are Irish or Irish-American, are closely associated with Irish traditional music, and often performers. Others are Irish or Irish-American academics, poets, and writers, including the Philadelphia-based historian Dennis Clark. Of particular note are materials related to Dr. Moloney himself that provide an insight into his private and public lives. Included in this series is a small set of materials given to Dr. Moloney by fiddler and radio host Tommy Caulfield, including ledger books, correspondence, radio receipts, advertisements, and concert programs which provide documentation on the Irish Musicians' Association and the Irish Musicians' Union in Philadelphia beginning in the 1940s.