We have coined the term CAPS to describe cross-linked-Beta-amyloid protein species. CAPS, particularly dimeric forms, are highly neurotoxic. CAPS are also abundant in vivo, with dimeric species alone comprising as much as 40 percent of the total Abeta pool in late state AD brain. In this study we plan to screen compound libraries for potential therapeutic agents that attenuate the levels and/or cytotoxic activity of CAPS.