Mass shootings in schools raise important questions about how best to keep individuals safe and increase survivability in such situations. One of the most common techniques used is lockdown drills, which train individuals to build time and space between them and the threat. Despite their use in 95% of public K-12 schools nationwide, their efficacy is regularly called into question. The present two-pronged study examines the role of lockdowns both in practice (via drills) and in real-world events to answer this question. Findings indicate that continued training and drills builds and maintains skill mastery relative to correct deployment of the lockdown procedure, while the use of these tools in real-world events like mass school shootings can have a protective effect, leading to fewer injuries and deaths. Based on these findings, implications for policymakers and school administrators tasked with keeping students and staff safe are offered.