Using data from the School Survey on Crime and Safety (SSOCS), this report presents findings both on crime and violence in U.S. public schools and on the practices and programs schools have used to promote school safety. SSOCS collects data from public school principals about violent and nonviolent crimes in their schools. The survey also collects data on school security measures, school security staff, mental health services, parent and community involvement at school, and staff training. SSOCS data can be used to study how violent incidents in schools relate to the programs and practices that schools have in place to prevent crime. Data collection began in February 2020 and was conducted mostly using an online survey instrument. In March 2020, many schools began closing their physical buildings due to the coronavirus pandemic. This affected data collection activities. Also, the change to virtual schooling and the adjusted school year may have impacted the data collected by SSOCS. Readers should use caution when comparing SSOCS:2020 estimates with those from earlier years. The national sample for SSOCS:2020 was made up of 4,800 U.S. public schools. Of these schools, 2,370 elementary, middle, high/secondary, and combined/other schools responded. The results showed that nonresponding schools were significantly different from responding schools. However, the results also showed that weighting adjustments removed most of the observed nonresponse bias. [For the summary report, see ED621594. For the 2019 report, see ED596638.]