The U.S. Nuclear Regulatory Commission (NRC) is discontinuing proposed Draft Regulatory Guide (DG), DG-5033, "Security Performance (Adversary) Characteristics for Physical Security Programs for 10 CFR Part 72 Licensees." This DG was intended to support a new rule that would contain security requirements for Independent Spent Fuel Storage Installations (ISFSIs). Because the scope of the rulemaking has changed and the rule will no longer include the new requirements that DG-5033 was intended to support, the staff is discontinuing development of DG- 5033.