Ecosystem services from trees contribute to food security and sustainable development. Increasingly, organizations and institutions are recognizing the value of ecosystem services from trees on farms and in agricultural landscapes for food security and to sustain productivity. For smallholder farmers, these services can be important for securing livelihood strategies, especially for farmers living in poverty, as trees provide fodder, food, fuelwood, finance, and soil fertility. Smallholder farmers with less than 5 ha of land, produce around half of the world’s food, but many of them are living in poverty and suffer from food insecurity and malnutrition. Unsustainable land management and climate change are degrading the environments these farmers live in and depend on. As the remaining forests in the world are threatened by a growing demand for food, feed, fibre, and fuel, these farmers will face additional challenges, especially in a changing climate.