Seed systems shape what farmers grow, the diversity of crops available to communities, and the capacity of agricultural production to withstand climate and other shocks. Published in 2026 by the Swiss Agency for Development and Cooperation (SDC), this practical guide examines how seed systems can contribute to food security, nutrition, sustainable agriculture and rural livelihoods. It presents a pluralistic approach that recognizes the complementary roles of three systems: farmer-managed seed systems, which rely on practices such as seed saving and exchange; intermediate seed systems, which combine official variety recognition with simplified quality assurance; and formal seed systems, which distribute certified seed through public and private channels.

The guide outlines a four-step framework for designing seed system interventions: assessing the system and its wider context, identifying objectives and entry points, choosing appropriate intervention modalities, and developing interventions with stakeholders. It covers variety development and maintenance, seed production, dissemination, and the governance and enabling conditions that influence access to quality seed. Examples from Ethiopia, Uganda and Myanmar illustrate how coordinated investments across multiple functions can reinforce one another. In Uganda, local seed businesses expanded from 30 to 250 groups, while farmer seed producer organizations gained formal recognition and Quality Declared Seed was institutionalized as a recognized seed class.

Drawing on experience from development and humanitarian contexts, the guide emphasizes context-sensitive responses, farmer participation, gender and equity considerations, and monitoring of both intended and unintended effects. It also highlights the need to balance productivity gains with agrobiodiversity conservation and to strengthen existing seed channels rather than displace them. The intended audience includes development practitioners, policymakers, researchers and organizations working to improve seed security and food system outcomes.