Visual assessment of brain FDG PET data represents a fundamental skill, independent of the particular clinical indication toward which it is being applied. In our imaging facility, we routinely employ a systematic approach for evaluating regional metabolism throughout the brain. In addition, beginning in 2004, software tools approved by the Food and Drug Administration for quantifying relative regional activity became available to assist with that evaluation. This chapter first describes key aspects of a skilled visual assessment, and then examines methods of regional quantification that are practical in typical clinical environments, and, finally, illustrates an approach toward scan interpretation that integrates the visual and quantifying information present in clinical PET scans.