A companion piece to the final report of the Safe School Initiative of the United States Department of Education and the United States Secret Service, the threat assessment guide reviews certain findings developed from the Initiative’s study of 37 targeted school shootings which occurred between 1974 and 2000. The findings that formed the basis of the threat assessment included evidence that targeted school violence was rarely impulsive, that students who carried out these attacks typically planned the attacks in advance, that this planning behavior was often observable, and that usually other students were aware that the attack was being planned. The purpose of the guide is to provide a document that provides a process for pre-attack identification of threats and a methodology for assessing these threats. Basic principles used by the Secret Service in other types of threat assessments and interventions were applied to the school environment. The guide includes information on how to implement a threat assessment process, how to conduct a threat assessment and how to manage a life-threatening situation. 22 notes, appendix