Alzheimer disease (AD) is the most common type of dementia and will become increasingly prevalent with the growing elderly population. Despite established clinical diagnostic tools, the workup for dementia among primary caregivers can be complicated and specialist referral may not be readily available. A host of AD diagnostic tests has been proposed to aid in diagnosis, including functional neuroimaging such as positron emission tomography (PET). We review the basis for FDG-PET and PiB-PET, as well as available operating statistics. From this we advise scenarios for use of PET in primary settings and referral centers, approach to its interpretation, and outline a clinical prediction model based on findings.