Identified by DeMille as "Personal," this group of 196 boxes begins with 22 boxes dealing with the research and writing of the posthumously published The Autobiography of Cecil B. DeMille (Englewood Cliffs, N.J.: Prentice-Hall, 1959), edited by Donald Hayne. The files are arranged chronologically by year, and items within each year are arranged alphabetically by subject or name. Over time, the organization of some of the files deteriorated into groups of unrelated records. Therefore, files from later years reveal little or no formal organization.

Included in the autobiography research files are extracts from DeMille interviews conducted by Art Arthur (identified occasionally as "AA" in certain files) and by Donald Hayne during the mid-1950's. The typescripts were than identified by subject, cut up, and filed by subject or name. No complete transcripts remain intact, nor do the original tapes exist. Following transcription, tapes were unused and then discarded. Correspondence with the editors at Prentice-Hall is included among the files as well as typescript chapter drafts by Hayne and Arthur.

A major section deals with personal correspondence from 1915 to 1959. Often these files, arranged alphabetically, are identified as "General" and "Miscellaneous." General files deal with individuals and situations known to DeMille, ones in which he evidenced a continuing interest. Usually, the files identified as "Miscellaneous" contain anonymous letters, unsoliciting offers of products or services, and applications for employment. The files deal with a wide range of subjects: political issues, Paradise Ranch, investments and personal matters. Notes written by DeMille and members of his staff, while on the set or at other times, between 1932 and 1958 comprise a brief section.

A body of correspondence deals with financial records and correspondence dating from 1907 to 1964. These records contain financial ledgers, bank books, and paid bills. Also included is a series of boxes documents motion picture costs and gross receipt calculations.

Another section contains inventories, lists, and indexes of various kinds. They include: screening books (1949-1959) that contain titles of motion pictures shown at the DeMille home, complete with DeMille's reactions and comments; indexes to actors who appeared in DeMille's motion pictures over the years; desk calendars for DeMille and many of his staff (1932-1959); appointment books (1942-1958); and an index to phonograph records in his personal collection.