The Department of Homeland Security (DHS or the Department) invites public comment on the Advance Notice of Proposed Rulemaking (ANPRM) for potential revisions to the Protected Critical Infrastructure Information (PCII) regulations that provide the Department with the authority to establish uniform procedures for the receipt, care, and storage of Critical Infrastructure Information voluntarily submitted to the Department. For the purpose of maturing the program, DHS is initiating this rulemaking process to help it identify how to enhance the PCII regulation more effectively in achieving its regulatory objectives. DHS believes that after nine years of experience implementing the PCII program, DHS has gained first-hand insight on lessons learned, and that the ANPRM process provides expanded opportunities for the Department to hear and consider the views of interested members of the public on their recommendations for program modifications.