Interstate (D) hired Gilmer (P) as manager of financial services. As required by his employment P had registered as a securities representative with several stock exchanges, and that application stated that P had agreed to arbitrate any dispute, claim, or controversy arising between him and D according to the bylaws of the organizations with which he was registered. P was terminated and filed a suit for age discrimination under 29 U.S.C. ¤621. D moved to compel arbitration. That motion was denied in that the district court felt that age discrimination claims were protected from waiver of a judicial forum. The Court of Appeals reversed. The Supreme Court granted certiorari.