Fonds comprises Ronald St. John Macdonald's records regarding his personal, academic, and professional activities as a jurist, judge, and professor. Records include those related to Macdonald's involvement with Osgoode Hall, University of Western Ontario, University of Toronto, Dalhousie University, the European Court of Human Rights, the Hague, Peking University, World Academy of Arts and Science, Canadian Council of International Law, United Nations, Institute of International Law, African Society of International Law, British Institute of International Law, Canadian Institute of International Law, International Law Association, and others. Records types include correspondence; meeting minutes and agendas; research materials; photographs; newsletters; newspaper clippings; manuscripts; and off-prints.

Collection contains both original records and reproductions of materials related to Reverend Thomas McCulloch. Items include a glass plate etching of McCulloch, microfilm copies of his books, a sample of his shorthand, a ticket to a lecture given by McCulloch, and correspondence. The collection also includes a microform copy of a thesis written by a Dalhousie student about McCulloch.