The fonds consists of correspondence, diaries, log books, manuscripts, photographs, records books, gallery files, subject files, and printed material relating to Onleys career as an artist, including a record of work, sales, donations, and disputes with Revenue Canada about the taxation of visual artists. A sketchbook entitled "LEternite Cest De Trouver De Que Tu As Deja" combines the poetry of Claude Peloquin with 51 watercolours by Onley relating to his Arctic voyages.