Wiss, Janney, Elstner Associates, Inc. (WJE) is an American corporation of architects, engineers, and materials scientists specializing in the investigation, analysis, testing, and design of repairs for historic and contemporary buildings and structures. Founded in 1956, WJE is headquartered in Northbrook, Illinois, and has over 600 professionals in twenty offices across the United States. WJE personnel are specialized in architectural, structural, and civil engineering; materials conservation, chemistry and petrography, and testing and instrumentation.