Book excerpt: Livestock production systems are the result of an interaction between domestic animals and the environment, modulated by man, that dates back to Neolithic times. As a consequence of this interaction among the wide diversity of animal resources, natural habitats and population needs, very different farming systems have developed across the Mediterranean Basin. Understanding the mechanisms and effects of these relationships is key to design the farming systems best adapted to each condition, guaranteeing an adequate balance between target animal production and environmental outcomes provided by these systems. This is indeed a multidimensional topic, influenced by animal genetics, feeding resources, flock management, and economic and social aspects inside and outside the household. Therefore, this book focuses on the basis of the animal-environment interactions and the impact of human activities on the type and magnitude of these interactions. In this context, the issue of sustainability of livestock production is evaluated considering economic, social and environmental aspects. This book contributes to upgrade the state of the art in Mediterranean conditions, providing indicators and procedures of application across a wide range of systems, and hence of interest for researchers, students and professionals concerned with livestock production and the environment.