Welcome to the University of Chicago Library guide to information resources on Enrico Fermi and his role in Chicago Pile No. 1 (CP-1), the experiment which resulted in the first sustained nuclear chain reaction. This momentous experiment was shrouded in secrecy at the time it was conducted, but much information has since been made available to researchers and others interested in this event. This guide does not include all the resources available, but is intended as a starting point. If you have additional questions about doing research on early atomic energy, please feel free to contact me.