Dorothy Eck's papers consist primarily of correspondence, reports, resolutions, subject files, and news clippings that document Eck's activities in local government and Montana politics, particularly the 1972 Constitutional Convention in Montana.

Materials from Eck’s time as a Constitutional Convention delegate make up the bulk of the collection, consisting primarily of subject files and clippings arranged alphabetically by topic. Much of the correspondence is from constituents, with her reply often stapled to it. Correspondence of note includes interoffice letters among her and the other delegates about convention procedures and the drafting of articles. Many of the organizational records include Convention procedures, rules, reports, committee proposals, and memos. The subject files contain a robust collection of materials about the Montana Constitutional Society, the organization formed by the delegates after the Convention to stay in touch.

Materials from the League of Women Voters and Legislative subgroups are also organized by material types and are comprised mainly of correspondence, subject files, and clippings. Topics with the League of Women Voters materials include water rights and resources, elections, and executive reorganization. The Legislative materials focus mostly on court decisions and code of ethics reform.

The State-Local Coordinator materials focus primarily on her duties in that role. the bulk of the materials are subject files, and topics include a study by Northern Rockies Action League about the establishment of their training center; the Governor's Council on Management; the Montana Tomorrow program, which was part of her role as State-Local Coordinator to help local governments implement the goals of the new constitution and find funding for local government projects that encourage community development and growth; and the Towns of Tomorrow project (1974-1975), a pilot project of Montana Tomorrow intended to focus state and federal assistance on two small towns—Ennis and Plentywood.