Meech Lake Accord, 1987-1990
The Meech Lake Accord was a complex package of proposed amendments designed to address a number of concerns about the Canadian Constitution. Among other things, it proposed granting Quebec "distinct status" within the Canadian federation, and changing the amending formula of the Constitution by requiring unanimous consent of all the provinces for a greater number of amendments. The accord ultimately failed when the Manitoba legislature and the government of Newfoundland refused to assent to it.
Read more about this topic: Unsuccessful Attempts To Amend The Canadian Constitution