Series consists of typescript drafts, research materials, interviews, correspondence, publisher's gallies, promotional materials, and copies of articles by Brennan used for his non-fictional books and biographies.

Subseries consists of manuscripts, drafts, correspondence, articles, research and other materials related to Brennan's non-fiction works.

The fonds consists of administrative files including minutes, financial records and records for the Petroleum History Oral History Project, as well as sound and video recordings of monthly and annual general meetings which featured presentations from various guest speakers on the topic of Canadian petroleum resources. The fonds also includes interview files for the Oral History Project.