Introduction <p>The present study represents the first systematic review with a meta-analytic approach to evaluate the evidence on the implementation, content, and outcomes of Safe Zone training in educational settings.</p> Methods <p>Relevant articles were systematically searched in four scientific databases (e.g., PsycInfo, Scopus, Web of Science, and ERIC) from November 2023 to May 2024. We included original articles with relevant keywords associated with “Safe Zone, Safe Space” and “school or university”. Of the 1,029 records identified, 123 articles were included in the systematic review, of which six were analyzed with a meta-analytic approach.</p> Results <p>Within the systematic review, three main research areas were identified (with some overlap among articles): (A) <i>Safe Zone guidelines and best practices</i> (<i>n</i> = 110), (B) <i>Safe Zone contents</i> (<i>n</i> = 44), (C) <i>Safe Zone and outcomes</i> (<i>n</i> = 37). Most studies indicated positive relationships between implementing Safe Zone training and the positive effects on students’ and school staff’s well-being, and campus climate. A meta-analytic procedure was used to test the effectiveness of Safe Zone training in enhancing staff knowledge and their attitudes towards LGBTQ + people. Findings suggested that trained staff perceived higher levels of knowledge after training (<i>d</i> = 1.51; 5 studies) and more positive attitudes towards LGBTQ + people (<i>d</i> = 0.30; 4 studies). However, these findings are based on a few studies with limited sample sizes and should therefore be interpreted cautiously.</p> Policy implications <p>This research highlights the relevance of establishing Safe Zones training programs to create supportive environments for all students regardless of their sexual orientation and gender identity, by educating participants about sexual orientation, gender identity, and the challenges faced by LGBTQ + individuals.</p>