Caregivers play a critical role in the diagnosis and treatment of patients with ADRD. Indeed, caregivers’ around-theclock access to patient behavior and their intimate knowledge of patient functioning (and change in functioning) have led researchers to view these individuals as the proxies of choice for measuring noncognitive outcomes in ADRD clinical drug trials. The current review shows the role of caregivers in ADRD research to be evolving to a proxy ‘‘plus’’ capacity, whereby these individuals act not only to augment the assessment of patient variables, but also to self-report.