Neuroimaging has become increasingly important in the clinical assessment and diagnosis of dementia. Structural imaging with MRI and functional imaging techniques, such as positron emission tomography and single photon emission CT, increasingly are used to aid in the differential diagnosis and early detection of dementia. Imaging techniques also can track disease progression over time and may be useful to monitor treatment effects. The most important development in the field over the past decade is the ability to image amyloid in the brain. This technique will revolutionize patient management and care.