The Cornelia Day papers date from 1890 to 2004 and measure 9 linear feet. The papers are arranged in seven series: Biographical, Correspondence, Foreign visitors, Foreign travel, Community activities, Photographs, and Scrapbooks. The papers consist of correspondence, memorabilia, and photographs of the Shrauger and Day families as well as materials highlighting Day's commitment to the local, national, and international community.

The Biographical series includes information about Cornelia Shrauger Day, her husband Robert Day, and their sons; high school and college and memorabilia; and Shrauger family history.

The bulk of the Correspondence series is devoted to letters written by Cornelia Day to her parents from 1936 to 1984. Letters from her husband, Robert Day, before their marriage in 1940 and many written during World War II from the Pacific, where he served as an officer in the United States Navy, are part of this series. Also included are letters to Cornelia Day's father-in-law Wilbur Day, from her children Dennis and Ed, and from her sister Virginia Shrauger Jones. The entire set of the Christmas letters from Cornelia and Robert Day to their friends and family (1945-1994) completes the series.

The Days' involvement with the international community is revealed in the Foreign visitors series which documents, mostly in the form of correspondence, their participation in the Experiment in International Living and the Governmental Affairs Institute, a private cultural exchange organization in Washington, D. C. Folders for each of the more than sixty foreign visitors the Days hosted are arranged alphabetically. Photos and correspondence with some of these visitors can be found in the foreign visitors scrapbook and in the Visitor Service Program folders.

The Foreign travel series includes itineraries, correspondence, brochures and diaries of the Days many trips abroad, arranged chronologically by trip.

Cornelia Day's civic involvement is documented in the Community activities series comprising information primarily about her involvement in the YWCA and Planned Parenthood of Southeast Iowa. Materials from other organizations to which Day belonged, and histories she wrote of the Presbyterian church in Washington, Iowa, and the YWCA in that community complete the series. There is also considerable information about these activities in the Scrapbooks series.

The Photographs series contains an album kept by Cornelia Shrauger Day in the 193os and 1940s as well as photographs of the Day family and a sketch of Cornelia Shrauger Day drawn by her aunt Lilian Prentiss Schwartz.

The Scrapbooks contain a mix of family material and information about Cornelia Day's civic activities, as well as writings and letters.