China committed itself to reduce the carbon intensity of its economy (the amount of CO2 emitted per unit of GDP) by 40–45% during 2005–2020. Yet, between 2002 and 2009, China experienced a 3% increase in carbon intensity, though trends differed greatly among its 30 provinces. Decomposition analysis shows that sectoral efficiency gains in nearly all provinces were offset by movement towards a more carbon-intensive economic structure.