In 2013, VA became the first state to mandate the use of threat assessment teams in its K-12 public schools. We provide an account of the development and adaptation of threat assessment as a school safety practice and research on the Virginia Student Threat Assessment Guidelines in VA schools. We describe the state law and the question of whether suicide assessment should be considered a form of threat assessment. We then describe research on the statewide implementation of threat assessment and summarize results indicating overall positive outcomes for schools who are actively engaged in threat assessment, but qualitative findings from a needs assessment identified team training gaps as well as a need to orient the larger school community to the threat assessment process. We describe a series of online programs to educate students, parents, teachers, and other school staff about the threat assessment process. In conclusion, this paper presents some lessons learned in the statewide implementation of threat assessment as a safe and effective violence prevention strategy.