If the global community is to meet the commitment made in the Copenhagen Accord 2009, to keep the increase in global average surface temperature below 2°C, we urgently need to undergo a radical and fundamental change in how energy is supplied and used. As the case studies in the book have demonstrated, this will not be a straightforward process. Beyond the science and engineering challenges associated with decarbonising energy, significant governance and social issues also need to be overcome. With such large changes to our energy infrastructure, controversy is an inevitable part of the process of transformation. Indeed, controversy surrounding low-carbon energy developments can manifest itself in many ways and does not have to be a negative influence.