in this way cities may more effectively deliver on nationallevel environmental and economic objectives whether or not they are identified as green growth than nationallevel policies ultimately the key metric here concerns not employment growth in the green sector but the aggregate employment impact of moving to a lowcarbon economy as an indicator this must be seen as secondbest but a feasible secondbest increasing the supply and demand of regionally produced green goods and services which we define as those that reduce negative environmental externalities the impact on natural resources and the pressure on ecosystem services