This paper explores how New Zealand should address agricultural greenhouse gas emissions: methane and nitrous oxide. The starting point is the internationally agreed-upon goal of limiting global warming to below two degrees, and New Zealand’s commitment to contribute its ‘fair share’ to the international climate-change mitigation effort. The report focuses on the role of mitigating biological agricultural emissions within that, and how New Zealand could most cost-effectively mitigate its own emissions and contribute to the mitigation of agricultural emissions abroad. This paper complements a partner paper (Hollis et al 2015) that discusses the science relating to agricultural greenhouse gases.