Reference Re Secession of Quebec, [1998] 2 SCR 217 is a landmark judgment of the Supreme Court of Canada regarding the legality, under both Canadian and international law, of a unilateral secession of Quebec from Canada.

Both the Quebec government and the Canadian government stated they were pleased with the Supreme Court's opinion, pointing to different sections of the ruling.

The Supreme Court of Canada (SCC; French: Cour suprême du Canada, CSC) is the highest court in the judicial system of Canada. It comprises nine justices, whose decisions are the ultimate application of Canadian law, and grants permission to between 40 and 75 litigants each year to appeal decisions rendered by provincial, territorial and federal appellate courts. The Supreme Court is bijural, hearing cases from two major legal traditions (common law and civil law) and bilingual, hearing cases in both official languages of Canada (English and French).

The effects of any judicial decision on the common law, on the interpretation of statutes, or on any other application of law, can, in effect, be nullified by legislation, unless the particular decision of the court in question involves application of the Canadian Constitution, in which case, the decision (in most cases) is completely binding on the legislative branch. This is especially true of decisions which touch upon the Canadian Charter of Rights and Freedoms, which cannot be altered by the legislative branch unless the decision is overridden pursuant to section 33 (the "notwithstanding clause").