Topic 5 focuses on sweetpotato seed systems, exploring different types of seed systems in terms of the seed production systems and different actors involved. It explains the laboratory process used to produce clean versions of virus‐infected planting materials, and how these delicate plantlets are then reintroduced to the field conditions. It describes how planting materials can be multiplied and disseminated to provide thousands of households with cuttings of virus‐free and/or new varieties. Step‐by step instructions for designing and costing a planting material multiplication and distribution system are presented.