Several developing economies have announced carbon emissions targets for 2020 as part of the negotiating process for a post-Kyoto climate policy regime. China and India's commitments are framed as reductions in the emissions intensity of the economy by 40-45% and 20-25%, respectively, between 2005 and 2020. How feasible are the proposed reductions in emissions intensity for China and India, and how do they compare with the targeted reductions in the US and the EU? In this paper, we use a stochastic frontier model of energy intensity to decompose energy intensity into the effects of input and output mix, climate, and a residual technology variable. We use the model to produce emissions projections for China and India under a number of scenarios regarding the pace of technological change and changes in the share of non-fossil energy. We find that China is likely to need to adopt ambitious carbon mitigation policies in order to achieve its stated target, and that its targeted reductions in emissions intensity are on par with those implicit in the US and EU targets. India's target is less ambitious and might be met with only limited or even no dedicated mitigation policies.