Rapidly growing demand for livestock products worldwide is brought about by human population pressure, growing income and urbanization. Land use and human population pressures are leading to intensification and expansion in many livestock production systems. In addition, expansion of cropping into drier areas in forcing pastoral livestock production systems to relocate into still more arid lands. As a result of these changes new pressures on the environment are developing or could emerge and, therefore, should be of concern. This book addresses the trends and issues in livestock production systems and attempts to assess more objectively the role of livestock in environmentally sustainable agriculture. It can help organizations and professionals in finding orientation in the world's livestock sector that is becoming increasingly complex.