We consider two approaches to quantify New Zealand farmers’ ability to mitigate their farm’s environmental impact: The construction of marginal abatement cost curves and improvements in farm management practices. Marginal abatement cost curves can be constructed by combining information on the effectiveness of mitigation with cost data. However, we find that the available data is not sufficient to support this approach. We consider improvements in management practices using a distribution of farm production efficiency with regard to nitrogen and greenhouse gas (kg production per unit of emissions). Where differences in production efficiency are due to factors that can be managed by farmers, targeting less efficient farmers to encourage the adoption of management practices similar to those of the more efficient farmers is a potential mitigation strategy.