This presentation from ECHO Asia explores how to identify, preserve, and promote Neglected and Underutilized Species (NUS) — plant species that are often overlooked in modern agriculture but have strong potential to support food security, nutrition, income, and biodiversity. It discusses the causes of diminishing plant biodiversity, the importance of local and informal seed systems, and the value of involving farmers, markets, and communities in identifying useful NUS. It also provides field techniques like market surveys, interviews with cooks and farmers, seed swaps, and community-based assessments to discover locally adapted NUS.