Juvenile courts nationwide handle cases referred by schools for truancy or behavioral incidents. Since 2012, the National Council of Juvenile and Family Court Judges (NCJFCJ) has trained jurisdictions on strategies and policies to reduce the number of referrals to the juvenile justice system for school-based behaviors. The NCJFCJ has provided technical assistance to communities seeking to develop multidisciplinary teams to address school-justice issues, commonly referred to as School-Justice Partnerships (SJPs). A consistent lesson learned from working with various communities is that valid and reliable process and outcome data are not routinely collected or shared across key agencies within the SJPs. Accurate and complete data provide SJPs with a foundation to target their efforts, monitor implementation, and measure outcomes effectively. Poor data collection and management strategies can be counterproductive and result in inaccurate data, wasted time, and misinformed conclusions. This technical assistance bulletin provides guidance around what information to collect and how to use it to promote effective SJPs.