There is a growing body scientific evidence regarding the outcomes and impacts of agroecology. This knowledge brief aims to provide a set of evidence, based on a large-scale analysis of scientific articles (literature review, meta-analysis, models). There is a strong theoretical basis and empirical evidence that food security outcomes (availability, access, utilisation, stability) are as good or sometimes even better for agroecological systems than conventional alternatives. Four levels for agroecology supporting the positive impacts of agroecology on food security are analysed : crop diversification, legume- based systems, agroforestry and mixed crop-livestock systems. Crop diversification ins an effective strategy to improve food security by mobilising different biological mechanisms. Due to its biological characteristics for nitrogen (N) fixing, legumes are one of the most important levers for improving food security (both availability and food utilisation/nutrition) based on agroecological principes. Agroforestry contributes to food availability by recycling nutrients, to food stability by increasing the resilience of the farming systems and to food utilisation through better diets. Mixed crop-livestock systems contribute to food availability by recycling nutrients and to food utilisation through meat and milk consumption. As agroecology is more than a set of practices, this knowledge brief specifically focuses on two approaches with a high potential to increase food security and efficiently address environmental challenges. A set of evidence is analysed for integrated soil health management and agroecological pest management.