The impact of two greenhouse gas abatement policies on two Mediterranean-type farming systems, grazing dominant and cropping dominant, is examined. The policies analysed are; an emissions taxation policy and an emissions restrictions policy. For both farming systems the restriction policy is found to be more effective and economically efficient than the carbon permit policy. Absolute cost of abatement is less for the livestock dominant system but relative cost is greater, because of lower total farm profits. The analysis found that at predicted emissions permit prices, trees, if credited as a carbon sink, would be adopted by both farming systems to offset farm greenhouse gas emissions.