The Consolidated Appropriations Act, 2016 (Pub. L. 114-113) provided $75 million for the Comprehensive School Safety Initiative (CSSI, or the Initiative) and the Consolidated Appropriations Act, 2017 (Pub. L. 115-31) provided $50 million for CSSI. Senate Report 114-57 and Senate Report 114-239 instruct the National Institute of Justice (NIJ) to provide a report on the continued development of a strategy and model for comprehensive school safety. This report satisfies the reporting requirement for both FY 2016 and FY 2017. The Initiative, administered by NIJ, was launched in FY 2014. NIJ carries out this important initiative in collaboration and through consultation with subject matter experts from multiple relevant disciplines, including other executive branch agencies and Congress. NIJ has produced a report to Congress on CSSI in each fiscal year since its inception. CSSI is designed to improve the safety of schools and students nationwide by developing, supporting, and rigorously evaluating school safety programs, practices, and strategies. An important part of the initiative is the partnerships between school professionals and researchers to develop and test approaches that address the real-world safety needs and priorities of America's schools and students. This research-focused, practically-oriented approach is intended to produce knowledge with wide utility and applicability beyond the specific schools that are directly involved in the CSSI. This report describes the goals, guiding principles, activities, and accomplishments for CSSI, and reports on grants awarded in FY 2016 and FY 2017. Since FY 2014, the Comprehensive School Safety Initiative has been provided with $275 million and has funded 93 multi-year research and pilot projects that support the development and evaluation of school safety interventions in over 3,100 schools across the Nation. With the enactment of the Consolidated Appropriations Act of 2018, school safety resources will shift from research and evaluation to the purposes outlined in the Stop School Violence Act of 2018, including the purchase of equipment to harden schools, evidence-based training and technical assistance, the development of anonymous reporting systems, school safety assessments, and intervention teams. [For "The Comprehensive School Safety Initiative: 2015 Report to Congress. Awards Made in Fiscal Year 2014," see ED604733.]