BackgroundAdaptation is a key strategy to extend the reach of evidence-based interventions to prevent violence in new populations, but there is a dearth of practical case examples. The Good School Toolkit was developed by Ugandan NGO Raising Voices for use in primary schools (GST-P). We describe our systematic approach to adapting the GST-P for use in secondary schools in Uganda, and reflect on the utility of the process as well as limitations of existing adaptation frameworks.MethodsWe adapted the GST-P in four phases, which included: I) clarifying the logic model and core intervention components using a streamlined process; II) conducting formative research (cross-sectional survey, focus groups, etc.) to understand the new population; III) selecting and preparing new intervention components and modifying existing intervention components; and IV) pretesting new intervention components with teachers and students in Uganda.ResultsWe identified core components using a logic model. Formative research showed results largely in line with our apriori hypotheses. Teacher violence remained highly prevalent in secondary versus primary schools (> 65% of secondary students reported past year exposure), while peer violence significantly increased (secondary = 52% vs. primary girls = 40%, P < 0.001; secondary = 54% vs. primary boys = 44%, P = 0.009) in secondary versus primary schools. Significantly more secondary girls (51%) than secondary boys (45%) reported past year dating/intimate partner violence (P = 0.03). Inequitable, gendered educational practices emerged as a salient theme, perceived to heighten female students’ vulnerability to violence. In light of these findings, we made several adjustments to the adapted intervention. We strengthened existing teacher and peer violence intervention components. We also developed, pretested and revised new program components to prevent dating violence and promote ‘gender fairness in schools’. Finally, original activities were modified to support engagement with school administration and promote increased student agency in secondary schools.ConclusionsBased on our experience, it was difficult to apply mechanistic models to clarify the intervention logic of the GST-P, a complex multicomponent intervention, and simpler methods may be sufficient. Our team had high levels of contextual knowledge before the adaptation, and formative research to understand the new target population provided only limited additional insight. In similar situations, a simplified approach to mapping the core intervention components, qualitative research to understand the new target population, and pre-testing of new intervention components may be the most informative elements of systematic adaptation processes.