The initial clinical approach to suspected dementia involves asking the right questions of the patient and a knowledgeable family member or caregiver. These questions should focus on the nature of the cognitive problem (e.g., the onset, duration, and severity of memory difficulties). The clinical interview is supplemented with thorough examination of the patient's physical, neurologic, mental, and functional status. Once a diagnosis of dementia is established, the underlying cause should be identified by a standardized workup, including laboratory testing and, in most cases, neuroimaging. Genetic testing for the APOE epsilon 4 allele can help confirm the diagnosis in patients with late-onset familial or sporadic Alzheimer's disease.