|Location||Toronto, Ontario, Canada|
In 2009, the gallery moved to the Bloor and Lansdowne area in Toronto's west end. Previously the gallery had held homes at 29 Mercer Street (from which the name Mercer Union was derived), 439 King Street West, 333 Adelaide St. West, and 37 Lisgar Street.
Notable artists who have had an exhibition at Mercer Union include Sol LeWitt, George Bures Miller, Mark Leckey, Jeremy Deller, G. B. Jones, Mowry Baden, Bill Burns, Betty Goodwin, Jana Sterbak, and Geoffrey Farmer.
In 1993, Mercer Union was involved in a case of censorship. The gallery was raided by police in December 1993, and works by Canadian artist Eli Langer were seized. The artworks depicted children in sexual situations. The artist and organization faced allegations of violating Canada's child pornography laws, but the case was won and all charges dropped.
In 2008, Mercer Union exhibited work by Canadian artist Michel de Broin. The artist's “Shared Propulsion Car,” an old Buick stripped of its engine and interior, and then outfitted with a four-seat bicycle pedal and brake system, was confiscated by Toronto police after gallery staff took it for ride on Queen Street West. The driver was ticketed for operating an unsafe vehicle; however, the charges were dismissed after a court appearance. De Broin characterized the dismissal as a victory for “the right to go slow.”. The same artist's car was driven in New York City without controversy.
- Tyler, Tracey (April 1995). "Artist's sexual images ruled legal". Globe and Mail.
- "Police to File Charges Over Seized Works". Toronto Sun. 1993.
- Doolittle, Robyn (4 April 2008). "Artist beats ticket for 'driving' pedal car". The Star (Toronto). Retrieved 12 May 2010.
- Huber, Jordana (3 April 2008). "Pedal-powered Buick creator wins court fight". National Post.