This limited competition FOA is to continue the Alzheimer's Disease Cooperative Study (ADCS) as the pre-eminent Alzheimer's disease (AD) clinical trials consortium. The purpose of this FOA is to solicit the renewal application for the next 5-year cycle of the ADCS. The goals of this next phase are to continue to advance research in the development of interventions that might be useful for treating, delaying, or preventing AD, particularly interventions that might not be developed by industry.