The OAG focuses on acquiring, interpreting, and sharing art as well as acting as a cultural meeting place.

[4] The Gallery's opening was preceded by a survey exhibition of local art in 1975 in the Hall of Commerce Building at Lansdowne Park, including over 300 artworks by 156 artists.

[5] This exhibition was organized by artists Victor Tolgesy, Gerald Trottier, and James Boyd among others, and was one of the outcomes of the Visual Arts Ottawa coalition formed in 1974.

[6]: 264  In 1993 the Gallery's Board of Directors met for the first time and it was registered as a tax-exempt charity, as well as separating from the Ottawa Arts Centre Foundation and officially becoming its own entity.

[9] Designed by architect Robert Surtees and built in 1870, the Carleton County Courthouse was an important centre for local government and administration.

(Jack) and Isobel Firestone (née Torontow) in the 1950s, this substantial private collection of twentieth century Canadian art grew through their acquisition of works by artists from coast to coast, and was exhibited and stored in Belmanor, their home in Rockcliffe Park, Ottawa, that they shared with their four children.

Jackson, Lawren Harris, Arthur Lismer, Edwin Holgate, (members of the Group of Seven), Emily Carr, Alma Duncan, David Milne, and Norval Morrisseau.

[23] The OAG's Permanent Collection includes works by contemporary artists such as Pat Durr, Barry Ace, Lynne Cohen, Evergon, Annie Pootoogook, and Leslie Reid.