An Assessment of Four Divisions of the Physical Measurement Laboratory at the National Institute of Standards and Technology: Fiscal Year 2018 assesses the scientific and technical work performed by four divisions of the National Institute of Standards and Technology (NIST) Physical Measurement Laboratory. This publication reviews technical reports and technical program descriptions prepared by NIST staff and summarizes the findings of the authoring panel. Table of Contents Front Matter Summary 1 The Charge to the Panel and the Assessment Process 2 Organization and Mission of the Physical Measurement Laboratory 3 Applied Physics Division 4 Quantum Electromagnetics Division 5 Time and Frequency Division 6 Quantum Physics Division 7 Key Recommendations Acronyms