State governments and other agencies are resources that have the potential to provide leadership and guidance about school-based threat assessment practices. However, accessing information regarding threat assessment-related state mandates and recommendations can be a challenging and a time consuming task for school personnel as there is no single database or resource where that information is housed. Via internet searches covering all 50 United States, as well as the District of Columbia and Puerto Rico, the authors of this study identified state statutes, requirements, standards, and other recommendations for school-based threat assessment. Currently, only one state unambiguously and explicitly mandates threat assessment procedures and threat assessment teams. However, at least five other states have other statutes, standards, or procedures that imply the need for school-based threat assessment. Additionally, at least 39 states provided a quality web-based threat assessment resource for schools. Twenty-three of those resources were posted on state departments of education or public instruction web pages. At least 21 states have developed specific state guidance documents on school-based threat assessment. These resources can guide school-based mental health professionals as they prepare for conducting threat assessments in the school setting.