Correspondence, clippings, committee notes, minutes, financial statements, executive reports, and newsletters pertaining to Yaddo, an artists' community in Saratoga Springs, New York. From the early 1930's, Cowley was a frequent guest at Yaddo, where he worked on portions of Exile's Return. He was an active member of the corporation through the 1980's, and served on several committees as well as the board of directors.

The bulk of this series consists of incoming and outgoing correspondence between Cowley and other members of Yaddo concerning the general operation of the organization. Executive reports prior to 1970 include financial statements; subsequent financial statements are filed separately. The Elizabeth Ames Accusation folder contains reports pertaining to the 1949 incident in which four Yaddo guests unsuccessfully called for the removal of executive director Elizabeth Ames because of her association with alleged Communists. Correspondence regarding this incident is filed within the individual correspondents' folders.

Original folder titles and comments were kept and filed under Original Folder Notes; oftentimes these have colorful or illuminating descriptions of the folder contents.

See also Series 1: Correspondence, Series 2: Working Files, and Series 3: American Academy Files, under the names of individuals, for more correspondence from those parties.