We assessed the potential influence of β-amyloid imaging on clinician diagnoses and management of patients with memory loss. We surveyed 315 clinicians, assigning each a vignette describing a hypothetical patient with symptoms of unexplained mild cognitive impairment, possible Alzheimer disease (AD), or young-onset dementia. Vignettes reported "positive," "negative," or no β-amyloid imaging information. We assessed imaging's influence on diagnosis (AD contribution to symptoms), diagnostic confidence, and patient management. Compared with clinicians receiving no imaging, clinicians given positive imaging results more often attributed symptoms to AD [odds ratio (OR)=5.91; 95% confidence interval (CI), 1.25-27.97]; clinicians given negative imaging were less likely (OR=0.10; 95% CI, 0.04-0.21). Clinicians identifying AD as contributing to symptoms more often recommended acetylcholinesterase inhibitor (AChEI) (OR=18.59; 95% CI, 6.86-50.36) and N-methyl-D-aspartate receptor antagonists (OR=3.63; 95% CI, 1.78-7.39). We found that negative imaging reduced AChEI recommendations. Positive imaging reduced recommendation of β-amyloid imaging for future patients. In conclusion, β-amyloid imaging can influence diagnosis, prescriptions, and patient management.