The WCT supplements the Berne Convention in several important respects. As this Subcommittee is well aware, several aspects of this agreement required changes to U.S. law--notably those aspects of the agreement relating to circumvention of technological protection measures and tampering with copyright management information.(4) Another provision of the WCT, which did not require any change in U.S. law, requires parties to grant copyright owners an exclusive right of communication to the public, including making a work available to the public on demand.(5)