Sustainable livestock farming and improved product quality are societal concerns that currently influence the direction of research on livestock farming systems (LFS). Livestock feeding plays a major role in animal health and product quality. Systems research into these areas is an effective way of studying the complex interactions between feeding, health and management. The growing emphasis on new objectives such as landscape preservation and organic livestock farming also calls for systems research. This book focuses on the following topics: advances in modelling animal nutrition and health, and their interactions at farm level; advances for managing LFS for land use sustainability in contrasted environments, with a special emphasis on mountain conditions; improvement of health, welfare and production in organic livestock farming; and decision support systems and models for improving livestock farming management.