DRR, in conjunction with Building Technology, Inc., Weidlinger and Associates, and Battelle Institute, will develop a manual on "Incremental Security Enhancement for Existing Commercial Buildings." This will provide design guidance to incrementally modify existing commercial buildings in order to deflect potential terrorist attacks involving explosive, chemical, biological or radiological agents. The purpose is to reduce public exposure to terrorist risk in commercial buildings in the United States. The DRR led project team will apply the unique experience of existing building evaluation and rehabilitation gained in the development of the Incremental Seismic Rehabilitation series of manuals and thenetwork of architects, engineers and building owners related to rehabilitation of retail, office, multi-family residential and hotel buildings.