The demonstration was sponsored by the Technical Support Working Group (TSWG)--an interagency organization that includes the National Institute of Justice (NIJ)--that is responsible for developing counterterrorism technologies. The demonstration was structured to evaluate various technologies and systems for producing imaging of objects and movements behind standard sheetrock walls with wood interior studs, plaster walls over lathe, a 24-inch reinforced concrete wall, a tile wall, cinder block, wood walls, and multiple interior walls. Six companies/organizations were able to provide operational systems that could be evaluated in a neutral environment under a standardized demonstration protocol. Evaluators concluded that through-the-wall surveillance technology has great promise, but there is room for improvement; for example, most of the systems were too large for field use by anticipated users. Also, more user-friendly displays are needed. NIJ is working with TSWG and Raytheon Systems Company to address these issues.