A quarter of the Peruvian population is native to one of the 55 indigenous groups present in the country, 51 of which live in the Peruvian Amazon. In this area, over half of indigenous children under 5 years old suffer from chronic undernutrition and anaemia, far above national average. High levels of poverty, food insecurity and child mortality and morbidity still persist amongst indigenous peoples in Peru. The health systems of the diverse indigenous populations of the Peruvian Amazon are based on an integrated understanding of the world, whereby forests support plant and animal biodiversity, provide adequate resources for good nutrition and health and hold significant cultural value. For these Amazon-dwelling populations, agroforestry is the closest agricultural practice to traditional indigenous ways of life because it supports high levels of cultivated and non-cultivated biodiversity. There is limited evidence of the impacts of agroforestry on human nutrition and health and, to date, inter-disciplinary research integrating agroforestry, nutrition and health has not been done in the Peruvian Amazon. In this context, the GAIN project has been funded since 2019 by Fondecyt (Peru) and the Newton Fund (UK) and seeks to co-design culturally-appropriate and gender-sensitive agroforestry options and food-based recommendations that have the potential to sustainably improve nutrition and health of indigenous populations in the Peruvian Amazon. Its use of intercultural models represents a major step change in the development of approaches to address chronic undernutrition and high anaemia prevalence in indigenous populations, and buffer them against future nutrition and health shocks. Based on an evidence-led approach, the GAIN project documents how socio-cultural norms, gender dimensions and the food environment mediate the multiple pathways through which agroforestry practices contribute to maternal and child nutrition and health. Understanding these dynamic processes i