Globally, dairy and beef production has become an extremely competitive industry. While the world milk production is predicted to grow significantly by 2020 with the emergence of new consumers in developing countries, milk and meat production in the more establish markets now has to fulfil new societal needs beside the simple product supply: animal health, food safety, and production environmental impact are some of them. At the same time, the recent extreme increase in feed costs emphasizes again the key role of rumen and gut efficiency management in production economics. All these new thematic topics are central to the proper management of ruminant digestive process. Producers must endeavour to seek new technologies to improve production efficiency, animal health and production costs while keeping in mind the environmental impact these changes make. ‘Gut efficiency; the key ingredient in ruminant production’ brings together some of the world’s leading authorities in the field of ruminant nutrition and production. It considers the importance of digestive health in performance achievement together with novel strategies to manage it. It is aimed at nutritionists, veterinarians and animal producers as well as students and researchers studying animal and applied biological sciences.