Agricultural production accounts for 10–12% of global annual greenhouse gas emissions, with livestock production (including sheep) being the most important contributing factor within this sector. The largest single contributor to agricultural greenhouse gas emissions is methane produced during enteric fermentation. This chapter describes the various approaches available to minimizing enteric emissions from sheep, including plant-based approaches and the use of additives in grazing sheep. The chapter also examines host-driven effects on the rumen and suggests future lines of development and research in this area.