"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)". This project will investigate why many small molecules self-assemble in dilute solution to form very long "1-dimensional" (1D) objects, thinner than a human hair, that organize into 3-dimensional (3D) networks. Events starting from the earliest moments when a few molecules come together to start the growth process and continuing until the 1D objects are fully formed will be probed experimentally, and models consistent with the results will be developed. Structural and dynamic changes during the assembly process will be characterized using techniques that correlate the temporal evolution of molecular and more macro (i.e., fiber) structures, as well as growth patterns. Appropriate theoretical calculations will be used to model the packing of molecules within fibers and will cover the large space and time scales involved in the growth of fibers. Although focusing on specific systems, the thrust of the research will be to generate global models with predictive powers. Learning how and why small organic molecules assemble into 1D objects and in 3D fibrillar networks will enable the inexpensive design and construction of new high-tech nanodevices. It will indicate how to promote beneficial biological functions (e.g., cytoskeletal filament formation) and how to impede neurodegenerative diseases that rely on fibrillar growth (e.g., Alzheimer's). Also, an outreach project will bring practical examples of fiber and gel formation to students at a Washington, D.C. high school. The modules will be placed on the web for general use.