In Chapter 12, C. De Vincenti argues that the concrete implementation of the Next Generation EU strategy and the recent aggravation of the energy security question have brought a crucial issue to the fore: what is really meant by the Do No Significant Harm (DNSH) principle. Up to now, EU documents have adopted an extremely restrictive interpretation of the principle that hinders essential investments for the green transition and the diversification of energy supplies. In this chapter an alternative interpretation of the DNSH principle is proposed, which could transform it into an effective lever for the required fundamental investments.