Alzheimer's disease is a chronic and progressive neurodegenerative disorder characterized by cognitive and functional deficit and by behavior disturbance. This disease presents a major clinical and social challenge. Increasing evidence suggests that early intervention can delay the progression of the disease and improve symptoms and cognitive functioning. Recent research focuses on genetic susceptibility. Genetic testing may eventually prove to be useful in identifying persons at risk before the onset of symptoms, but at this stage, this testing plays a limited role in identifying and confirming the diagnosis and in genetic counseling. The diagnostic work in all suspected cases of dementia should be started by family physicians; confirmed cases should be treated as soon as possible by the family physician or referred to a psychiatrist or neurologist for appropriate treatment. Donepezil, new cholinesterase inhibitors, and vitamin E have proved effective in delaying progression of Alzheimer's disease.