Despite a federal division of powers and entrenched constitutional rights provisions, parliamentary sovereignty is accepted in Canada as a significant legal phenomenon. The traditional understanding inherited from Britain is that Parliament remains legally free at all times to make or change any legal rule that it wants. This chapter recounts the story of how that understanding has been adapted to the Canadian constitutional context. It also discusses Canadian experience with the problem of a Parliament binding its successors, including certain qualifications that are now brought to the uncompromising view attributed to constitutional scholar A.V. Dicey. Finally, it examines the question of what official bodies, in addition to courts, are recognized by Canadian law as being able to decide that a statute is invalid.