Sierra Leone is facing a range of climate and environmental risks that directly affect human security. Human activities, including environmental crime, are further undermining protective ecosystem services and destroying carbon sinks, contributing to the cycle of degradation and accelerating the effects of climate change. Overall, this stocktaking study has found significant potential for prevention and stabilisation programming to improve service delivery of security institutions with regard to mitigating the impact of climate and environmental risks on communities and the environment, as well as strengthening social cohesion and contributing to sustainable peace. In addition to the more practical recommendations for international partners and the Government of Sierra Leone that are included in the report, several of the conclusions have broader relevance for security sector governance and reform (SSG/R), prevention and stabilisation programming across a range of regional, environmental and security contexts, and will be further explored in the other countries in the stocktaking study. This is an executive summary of the full report.