[2] It was preceded by Save Montreal, a volunteer group co-founded by Michael Fish after the controversial demolition of the Van Horne Mansion by developer David Azrieli in 1973.

[3] Heritage Montreal played a key role in efforts to halt demolition and redevelopment in the McGill Ghetto, also known as Milton Park.

Because of the efforts of the volunteers of Save Montreal, the Commission des Citoyens Pour l’Avenir de Montréal begins hearings on May 29, 1976, and adopted guidelines on July 6, 1978, that require "due consideration" to the architectural qualities of residential buildings before issuing demolition permits.

In 2001, Heritage Montreal suggested that Quebec's municipal reforms should include heritage-conservation and public-consultation bodies, Conseil du Patrimoine and Office de Consultation Publique, in the updated city charter.

[7] In 1985, SNC announced its plan to replace the CBC/Radio-Canada transmission mast on Mount Royal with a 300 metres (980 ft) tall tower topped by a restaurant.

Les Amis de la Montagne (Friends of the Mountain) formed in 1986 to advocate for the preservation and enhancement of Mount Royal.

On March 9, 2005, the Government of Quebec granted double heritage protection status for the first time, decreeing Mount Royal a historic and natural district.

In an out-of-court settlement, the owner committed to developing and enhancing the property but instead abandoned the mansion and surrounding land for more than 25 years.

[12] On February 16, 1999, Heritage Montreal asked the Ministry of Culture and Communications to assign historic monument classification for the Art Deco restaurant on the 9th floor of the former Eaton’s department store.

The iconic milk-bottle-shaped Guaranteed Pure Milk water tower was restored with its original painted inscriptions.

In 1985, more than sixty students from Quebec and elsewhere enrolled in a summer course about renovation and restoration, organized by Heritage Montreal and Université de Montréal.

In 1986, a school bus became Heritage Montreal's Archibus, taking classes on architectural and urban discovery tours.

Heritage Montreal, in collaboration with the Ministry of Cultural Affairs, published four technical guides on renovating traditional masonry, windows, roof coverings, and facings.