Advances in neuroimaging over the past 2 decades are products of breakthroughs in imaging technology, developments of more powerful computers and image-processing software, and expanding knowledge in basic and clinical neuroscience. In addition to the insights into normal brain structure and function that such methods provide and the information that can be gained from disease-related changes in structure and function, the promise of achieving diagnostic specificity through neuroimaging lies with the potential identification of pathognomonic proteins. Recent advances in imaging beta-amyloid plaques, one of the hallmarks of Alzheimer disease, offer such a technological breakthrough and the possibility for more efficient assessment of antiamyloid interventions as well as specific noninvasive diagnostic capabilities.