Part 1 of the C.L. Harrington Papers consist primarily of correspondence, memoranda, subject files, resource files, photographs, and ephemera covering the period 1909-1966. The bulk of the correspondence is related to Harrington's forty-eight year career with the Wisconsin Conservation Department. There is relatively little personal correspondence per se. The correspondence covers four rather distinct periods: Correspondence during his college days, 1909-1913, mostly with his parents; correspondence and related papers from the First World War years; correspondence for the period 1920-1958, primarily concerned with Wisconsin Conservation Department matters; and correspondence, 1958-1966, after his retirement. The Conservation Department group is essentially routine in content, but does indicate the nature of the internal workings of the department, especially for the years from 1945 through 1955. See especially the 1954 exchange with Commissioners John O. Moreland and Charles P. Smith for a good illustration of this. After Harrington's retirement, the correspondence is centered around his fight against the “sticker plan” and his work on the Natural Resources History Project.

Included in the Harrington papers is the correspondence of E.M. Griffith, State Forester of Wisconsin from 1904 to 1916.

The memoranda files, 1931-1964, record the day-to-day internal workings of the Wisconsin Conservation Department. Again, see especially memoranda for the 1954 period. The subject and resource files contain material pertaining to sundry aspects of Harrington's work including material assembled for the Natural Resources History Project. Subject headings are general and much material is in miscellaneous files.

The clipping files contain newspaper articles on all aspects of conservation, particularly in Wisconsin. There are a large number of clippings dealing with the 1954 controversy.

Other items in the collection are class notebooks kept at the University of Michigan; a personal expense ledger; a plat book used in early Wisconsin Conservation Department work; and a daybook, journal, and account book recording financial transactions of Harrington's father's livery stable in Hurley.