The collection consists of three series, CORRESPONDENCE, SUBJECT FILES, and MICROFILMED FILES. Most valuable for tracing the organizational history of the National Committee in the CORRESPONDENCE series are the letters of staff members and general staff memoranda and annotated clippings. Except for staff correspondence, identified by the staffer or office corresponding, the letters in this series are the files of executive director Frank Wilkinson. Wilkinson's personal correspondence is filed separately under his name. For Wilkinson's civil liberties activity before the formation of the National Committee, the letters of the Citizens Committee to Preserve American Freedoms and the National Emergency Civil Liberties Committee are of greatest value. Major organizational contacts of Frank Wilkinson and the National Committee include the American Civil Liberties Union and its state chapters, and the Southern Conference Educational Fund, most of whose correspondence can be found in the letters of Carl and Anne Braden or Mike Honey of the Southern Regional Office of NCARL. Also of note in the series is the correspondence of the National Committee and others to members of the United States Congress concerning civil liberties issues. In this area, the correspondence with Representative Robert Drinan of Massachusetts is the most extensive.

The SUBJECT FILES include newsletters, financial records, and mailings of the National Committee and its regional offices. Material in these areas is most complete for the national office, the Midwest Regional Office (Chicago Committee to Defend the Bill of Rights), and the Southern Regional Office. Also of importance are the hearing files, documenting various HUAC investigative hearings in the 1950s and 1960s, and legal, legislative, and research files. The legal files include legal documents and analyses for a number of civil rights, civil liberties, and anti-HUAC court cases and issues of concern to civil liberties organizations. The legislative files contain research and clippings concerning various “repressive” legislative proposals. Of these, the most extensive collection, including a tape recording of a Wilkinson speech, concern revisions of the federal criminal code and Senate Bill 1. Other research files contain various reference materials on HUAC and organizations opposed to it. Special files include writings and advertisements produced by the National Committee and extensive mailing lists of the organization. The notes files contain Frank Wilkinson's written comments on telephone conversations, field trips, and meetings; and appointment calendars indicate Wilkinson's busy travel and meetings schedule. In the materials under Wilkinson's own name, information is included about his suspension from the Los Angeles Housing Authority, his subsequent career, speeches and writings, and his field trip schedules and speaking advertisements.

Also in the Subject Files are photographs and ephemera (filed under Photographs). These include images of protests against HUAC, a freedom march in Nashville in 1963, and images of American Nazi Party members supporting HUAC. Ephemera include material and posters made by the organization.

MICROFILMED FILES contain miscellaneous materials relating to Wilkinson's files and activities.