This paper，based on the report “Better Growth，Better Climate：The New Climate Economy” issued by The Global Commission on the Economy and Climate，tried to explore the growing contribution of cities both to the world economy and carbon emissions. It reviewed the most common form of urban expansion across countries today，and examines an alternative growth pathway，giving special attention to urban form，transport，and initiatives which boost short to medium-term resource productivity. The paper discussed the kinds of urban policy frameworks needed to scale up that alternative pathway，through planning policy，pricing instruments，fiscal and finance mechanisms，governance，and legal powers.