Because of the growing population and negative effects of climate change, smallholder farmers in Africa are developing new techniques that can improve crop productivity. This article describes four national case studies where farmers have started applying the principles of evergreen agriculture, which is defined as the intercropping of particular tree species into annual food crop systems. Integrating trees helps improve soil nutrient supply and soil structure, increase farmer incomes from food, fodder, fuel, and fiber production, improve water infiltration, and increase biodiversity above and below ground. Because of these natural benefits, evergreen agriculture proves to be an effective approach for addressing the issue of food security in Africa.