Participatory action research generates knowledge for Sustainable Development Goals

New approaches to generating knowledge are needed to achieve the UN Sustainable Development Goals (SDGs). Participatory action research (PAR) builds on and expands the scientific process through engagement of scientists (ecological, agricultural, and social) with stakeholders in a systematic manner. To illustrate iterative co-learning cycles, we report on two decades of PAR in rural communities in Malawi. Novel findings include the expansion of agricultural diversity beyond agroforestry to meet farmer requirements while enhancing redundancy and supporting a broad range of functions. Insights from farmers facilitated identification of the value of intermediate growth habits (such as those of shrubs and vines) as "goldilocks" crop types that tighten nutrient cycles in mixed farming systems while providing multiple harvests of nutritious seeds and forage. This illustrates how PAR involves co-design with stakeholders and learning by doing, to meet local needs and mediate trade-offs, as well as generate knowledge that addresses SDGs.