The papers of Congressman Clarence D. Long (D. MD) include material from Long's twenty-two years (1963-1985) as the elected Representative from the 2nd District in Maryland. In the collection are office files, speeches, press releases, issue mail, legislative files, photographs, artifacts, research materials, news clippings, correspondence, reports, and travel information. The bulk of the material represents the years 1970-1979.

There are no personal papers in the collection. There are no papers related to Long's teaching career at Johns Hopkins in the collection.

The papers provide a view of congressional work during a period when the United States was dealing with diminished sources of energy, the spread of nuclear technology, increased attention to foreign aid, human rights' questions in Eastern bloc countries, and civil unrest at home. Long's work in Congress focused on many of these issues.

The largest series in the collection is Series 1: Office Files (1961-1984) which is separated into three subseries: Administrative, Towson Office and Washington Office. Together with Series 5: Press Office (1963-1983), and Series 7: Legislation (1966-1982), it is possible to get an integrated view of the work of Long and that of his staff on national and local issues. Of particular interest in the collection is Series 3: Projects (1966-1985) which details Long's involvement in two controversial Maryland projects - Subseries 1: Hart-Miller and Subseries 2: Bay Bridge. Of interest too is Series 6: Issue Mail (1964-1977) that includes correspondence related to the concerns and interests of constituents and many letters that offered issue-related opinions. Series 5: Press Office contains a large selection of printed newsletters that form a detailed chronology of Long's daily/weekly work in Congress. Known well for his constituent service, the photographs in Series 8 (1964-1984) document Long's many visits to schools, industrial sites, community centers, and civic events. Correspondence, notes, and project information from the joint meetings of Maryland senators and representatives on behalf of the state are included in Series 2: Maryland Delegation (1974-1979).