Since 1959, the National Institute of Standards and Technology (NIST) has annually commissioned the National Academies of Sciences, Engineering, and Medicine to assess its various measurements and standards laboratories. This report appraises the Physical Measurement Laboratory (PML), assessing four divisions of PML situated at the NIST Boulder campus: the Applied Physics Division, the Time and Frequency Division, the Quantum Electromagnetics Division, and the Quantum Physics Division. The report compares the caliber of research at PML with similar international programs to determine whether programs adequately align with its objectives; assesses the range of scientific and technical expertise available within PML; considers the budget, facilities, equipment, and Human Resources to bolster PML technical endeavors and contribute to the fulfillment of its goals; and assesses the efficacy of PML methods for disseminating the products of its work.