It is important to stress that the results presented are dependent on the way the greener sectors are approximated. Due to lack of primary survey data of the ‘real green economy’ the above proxies are used to specify the green sectors. This raises some concerns. For example, it is found that the green specifications in terms of the ten percentile of energy and resource efficient industries are highly correlated with higher labour productivity, notably in the service sector. That is, the most resource efficient companies also have the highest labour productivity.