Against the background of some of the more notable changes in English family law since the publication of Sir William Blackstone's Commentaries on the Laws of England, this article questions the justification for the survival, especially in its application to financial matters, of the principle that marriage creates a legal status the incidents of which the parties are debarred from amending. It concludes that, while the judicial imposition of a principle of equal division of the parties' assets can be justified, the law's refusal to allow the parties to regulate the financial consequences of the ending of their partnership by private agreement is no longer acceptable and that legislation is accordingly required.