A growing body of empirical evidence supporting the minority threat theoretical framework, which predicts harsher social controls in places with proportionally more minorities, indicates that restrictive security policies and practices are likelier to be imposed in US schools with larger percentages of Black and Latino/a students. Yet inconsistencies across studies have made the relationship between student composition and school security less clear than the findings of minority threat research measuring the association between student racial and ethnic composition and student discipline. In this chapter, we argue that these mixed findings predicting restrictive school security are attributable to the fact that certain security measures are used as a method of controlling the misbehavior of students, while others aim to protect those students and others from outsiders. To fully understand how minority threat is manifested in educational institutions—particularly at the high school level—the type and orientation of individual school security programs needs to be taken into account. A modest number of recent studies have examined to what extent particular security strategies are bundled in distinct categories that differentiate between student-based and external threats. We review these findings to advocate for school security research that distinguishes among physical control of students, surveillance of students, and protection of the school community from outsiders in order to better understand how minority students may be particularly disadvantaged by discriminatory policies and practices, a problem we urge policymakers to prioritize.