Agnes's brother George Richardson, who died fighting in World War I in 1916, left a legacy for her to use as she felt fit to stimulate development of the arts at Queen's University.

Agnes Etherington Art Centre holds over 17,000 works ranging from the 14th century to the present, placing it among the largest galleries in Ontario.

The Canadian historical collection includes works by: Andre Charles Bieler, Tom Thomson, Emily Carr, Lawren Harris, Arthur Lismer, Frederick Varley, Edwin Holgate, LeMoine FitzGerald, Fernand Leduc, Ozias Leduc, David Milne, William Ronald, Carl Beam, William Henry Bartlett, William Brymner, Kananginak Pootoogook, Pitseolak Ashoona The Contemporary Art Collection features visual art, with emphasis on the emerging generation of artists and works that reflect contemporary life and Canadian society.

The Contemporary collection includes works by: Charles Stankievech, Rebecca Belmore, Judy Radul, Brendan Fernandes, Luis Jacob, Vera Frenkel, David Rokeby, Norman White, Robert Houle, Shary Boyle, AA Bronson, General Idea, Ian Carr-Harris, Sarindar Dhaliwal, Andre Fauteux, Kim Ondaatje, Derek Sullivan The European Art Collection holds many paintings, prints, and drawings of exceptional quality and depth.

The European collection includes works by Rembrandt van Rijn, Willem Drost, Jan Lievens, Govert Flinck, Aert de Gelder, Gerbrand van den Eeckhout, Godfrey Kneller, Philips Koninck, Ferdinand Bol, El Greco, Dosso Dossi, Michael Sweerts, Luca Giordano, Georg Pencz, Sebastien Bourdon, Peter Lely, Joseph Wright of Derby, Raphael, Parmigianino, Guido Reni, Gustav Klimt, and Pablo Picasso.