Most of the world’s poorest smallholders depend on tropical roots and tuber crops as their principal source of food and nutrition. These species produce large quantities of dietary energy and have stable yields under difficult environmental conditions. The most important crops are cassava, sweet potato yam and the aroids; sharing important common traits such as bulkiness, post harvest perish ability and vegetative propagation. This book contains the most up to date information on the origin, genetics, physiology, agronomy, pests and diseases and post- harvest processing of these crops and provides ideas for further research and development. It is essential reading for students, researchers and horticulturists.