APS strives to guarantee the archival integrity of our online journals. In addition to the primary versions of record at our editorial office, we maintain multiple copies all of our content, distributed widely across the U.S., and we have also deposited the full APS content with Portico. We want to assure the scientific and library communities that we share its deep concern with this issue. The archive of APS journals is a priceless record of our subject, stretching from the present back to 1893, and is heavily used by active scientists, students, and historians. We are committed to its preservation and to enhancing its usefulness.