Dementia is a major public health problem in the United States and the world, requiring the expenditure of enormous economic and human resources. Dementia is common in the elderly, and, as the size of the aged population increases, the number of dementia victims will rise. Many dementias are fatal, producing the gradual erosion of intellectual abilities and eventual death of the patient. Demands made on family members and caregivers of dementia patients are extraordinary and often result in their emotional and financial exhaustion. Although basic science efforts are devoted to finding a cure for Alzheimer's disease (AD) and other dementing illnesses, there is an urgent need for research that has immediate applicability to the 4 million current dementia patients.