Peter Berkowitz served as a member of the Policy Planning Staff in the Office of the Secretary of State from January 2019 to July 2019, and as director of Policy Planning and senior advisor to the secretary from August 2019 to January 2021. During that period, he also served as executive secretary of the Commission on Unalienable Rights.

Much of the work of the Policy Planning Staff is classified and intended exclusively for the Secretary and senior State Department officials. Occasionally, the Policy Planning Staff supports, or undertakes on its own, projects also aimed at informing the public. Such was the case in 2019 and 2020 with the Commission on Unalienable Rights, which Harvard Law School Professor emerita Mary Ann Glendon chaired and whose work the Policy Planning Staff supported, and with "The Elements of the China Challenge," an unclassified paper written by the Policy Planning Staff.