Animal agriculture substantially contributes to the world economy by providing food, jobs, and financial security for billions of people. With increasing concerns over global climate change and pollution, efforts are underway to reduce the overall environmental impact of animal production. This document analyses emission of non-carbon dioxide greenhouse gases, an important segment of the environmental footprint of animal production. It has been developed by a team that included experts in animal/ruminant nutrition, manure and soil management, animal and whole-farm modeling, and animal reproduction. Over 900 publications focusing on nutritional and manure management mitigation strategies for methane (enteric or from manure) and nitrous oxide emissions were reviewed and analysed, and a synthesis of feed-, animal management- and manure management-based mitigation approaches and interactions amongst them has been presented. This document will help researchers, animal industry consultants, policy-makers, animal producers, non-governmental organizations, and other groups with interest in maintaining a viable and environmentally-responsible animal production sector to make sound decisions on selection and adoption of effective and economically feasible greenhouse gas mitigation practices.