The understanding and management of land resources used by grazing animals are of major importance to ecologists and agricultural and envionmental scientists. This book synthesizes a range of perspectives on grazing systems, drawn from plant science, animal science and ecology. It outlines the principles of herbage growth and competition, of animal nutrition and grazing behaviour, and of the interactions of plant and animal factors. Chapters on the management of grazing systems cover both intensive and extensive systems (including rangelands) from all major agroecological zones of the world. The book is suitable for advanced students and research workers concerned with plant science (especially grasslands), animal science (especially ruminants), and natural and agricultural ecosystems.