several g countries have cooperated with businesses working along specific value chains to help develop more innovative approaches to resource efficiency for instance the united kingdom france and germany have been actively supporting industrial symbiosis which engages economic actors in a network to foster ecoinnovation and knowledge sharing in order to make one operator s waste another one s material input japan is supporting the integration of industrial and urban symbiosis and through its ecotown programme given the multiple and diverse challenges along value chains these partnerships are potentially useful approaches that could be broadened and scaledup