The objective of this study was to provide a basis for future updates to the 2010 ASHRAE Performance Measurement Protocols for Commercial Buildings (PMP) through case studies. The PMP defines a standardized method of measuring and analyzing building performance in six categories: energy, water, thermal comfort, indoor air quality, lighting, and acoustics. We conducted case studies for five buildings following the PMP. Based on experiences following the protocol in this wide range of buildings, we assessed the validity, reliability, and practicality of the PMP and provided comments and recommendations for future revisions. Most of the measurement protocols at the basic level are reliable, practical, and valid. Many tasks at the intermediate and advanced levels, however, can be difficult to perform for some building types. Some of the tasks or measurement procedures were results from past research projects, and the software or tools recommended may not be readily available or fully supported. The measurement protocols at the intermediate level are only somewhat reliable and some of them are impractical. Most measurement protocols at the advanced level are complex and need to be performed by qualified or specially trained personnel and, thus, are impractical as a performance measure, except for specialized applications.