Robyn Morgan filed a nationwide collective action against her employer, Sundance, alleging violations of federal overtime law despite an agreement requiring arbitration. Sundance initially litigated the case in court, waited nearly eight months before moving to compel arbitration, and then sought to enforce the arbitration agreement after Morgan had incurred substantial litigation costs. The lower court applied an arbitration-specific waiver rule requiring proof of prejudice and found no waiver. The Supreme Court vacated that judgment. It held that the Federal Arbitration Act does not authorize courts to create a special waiver standard favoring arbitration. Arbitration agreements are subject to the same waiver principles as other contracts, and the court of appeals must determine whether Sundance knowingly relinquished its right to arbitrate under the ordinary framework. The Court remanded without deciding whether Sundance had waived arbitration.