"The Security Research Center (SRC) of the Defense Security Service (DSS) is conducting a program of research addressing government and industry procedures for security prescreening. Considerable emphasis has been placed upon developing tools and procedures for prescreening personnel at the time of enlistment into the military services. The SRC was tasked by the Director of Accession Policy, ASD (Force Manpower Policy) to determine potential measures for identifying military personnel associated with gangs and extremist groups and to design procedures for screening members of such groups during the enlistment process. We reviewed the literature on gangs and extremist groups and examined actual incidents within military contexts. We also reviewed the military's current responses to the problem to include existing directives, policies and procedures. Particular attention was given to the prescreening of military applicants during the phases of the enlistment process. The report documents the strong efforts of the Armed Services to address the issues attending gang and extremist group members but also concludes that these efforts could be enhanced through better guidance to relevant military and civilian personnel. We present four main recommendations for improving the military's gang and extremist screening efforts and point to some areas for future research."