Series consists of records pertaining to the anthology edited by Messenger and Bill New in 1993. There are four subseries: Research Notes subseries, Permissions subseries, Miscellaneous subseries, and Chronologies subseries.

Series consists of records about Messenger's participation in the Thesis Bibliography Series Project; this is an international bibliography of doctoral dissertations and masters' theses on selected writers. These records include correspondence and pamphlets.

Series consists of various correspondence, Christmas letters, and postcards received and sent out by Messenger to family, friends, colleagues, university libraries and publishers, including numerous hand-written notes written after Ann Messenger's death, found scattered among his correspondence files.

Series consists of notes and clippings about miscellaneous subjects.

Series consists of various miscellaneous records, including newspaper clippings, correspondence, newsletters, notebooks, travel logs and diaries, calendars, his diary as a homeowner and his interests in gardening and genealogy.

Series consists of offprints, reprints, photocopies and drafts of Messenger's essays, reviews, and articles. It also includes poems and limericks, notes, clippings, and correspondence.

Series consists of records about games and word puzzles created by Messenger. There are three subseries: Miscellaneous subseries, "Triple-Ploy" subseries, and Board Games subseries.

Series consists of colour photographs of William Messenger, his wife Ann and colleagues and friends, including pictures of his house. These are the photographs from the accrual in 2003 only. The series is arranged by year.

Series consists of Messenger's thesis presented to Cornell University and his doctoral dissertation submitted to the University of California at Berkeley (Box 13), including notes, correspondence, drafts and chapter notes.

Series consists of draft chapters, clippings, and notes of Messenger's work on his sea-themed novel called The Last Horizon.

Series consists of correspondence and personnel files on career and employment before Messenger's teaching career at UBC.

Series consists of notes, clippings, articles, reviews, revisions, and correspondence about Active Voice, a reader co-edited by Messenger and William New that was published in 1980 (1st ed.), 1986 (2nd ed.) and 1991 (3rd ed.).

Series consists of records about the Canadian Writer's Handbook, a writing guide co-authored by Messenger and Jan de Bruyn that was published in 1980 (1st ed.), 1986 (2nd ed.) and 1995 (3rd ed.). There are two subseries: Miscellaneous subseries and Subject subseries.

Series consists of records about Elements of Writing: a Process Rhetoric for Canadian Students (previously called "Essentials of Writing"), a writing guide co-authored by Messenger and Peter A Taylor and published in 1984. These records include correspondence, notes, drafts, reviews, permission forms, and revisions.

Series consists of records about Messenger's role as the Canadian National Editor of Conradiana between 1969 to 1980. These records include correspondence, notes, clippings, drafts and annotated copies of articles and reviews, and revisions.

Series consists of records about Messenger's miscellaneous editorial and review projects for Prentice-Hall Canada Inc. These records include an annotated policy document and correspondence.

Series consists of records of William Messenger's years with the UBC English Department. There are four subseries: Academic Teaching Career subseries, ComPost subseries, Course Materials subseries and Miscellaneous subseries.

Series consists of records relating to Gifts and Endowments from William and Ann Messenger, including correspondence, notices of awards, and book lists.

Series consists of Messenger's records as an undergraduate student at the University of Washington (1955-1956), a graduate student at Cornell University (1957-1959) and a post-graduate student at UCLA at Berkeley (1960-1966). These records include correspondence, student papers, artwork, designs and pencil drawings (thumbnail faculty drawings), manuscripts, notebooks, examinations, assignments, and transcripts.

Series consists of Messenger's works of fiction, detective story and murder mystery, including his manuscripts, outlines, notes, correspondence with publishers, and the final manuscript of A Necessary End, a murder mystery co-authored by Messenger with his wife Ann under the pseudonym of Edmund Carey.

The sous-fonds consists of correspondence, clippings, student records, student notebooks and papers, yearbooks, poetry, cookbooks, manuscripts, portraits, obituary notices, and tributes.