Work Package 4 of the ENTRUST project focuses on the policy landscape of energy transitions in the European Union. This deliverable provides an up-to-date picture of the current situation concerning the policies and regulations related to the energy system in a range of European countries. Key technological, social and market factors are scrutinised in order to understand the various energy policy frameworks in Ireland, Spain, the United Kingdom, France, Italy, and Germany. An analysis of the national dialogues in each of the member states is provided with a particular focus on the key public discourses, along with an assessment of the main barriers hindering low carbon measures, in each country. As the ENTRUST project looks at the human factor within the energy system, this deliverable seeks to identify the socio-political and economic components contributing to the political agenda on energy. The sustainable energy transition paradigm, that involves a gradual shift from conventional energy sources to renewable, more region-specific ones, is assessed using new institutionalism theory. This theory fits quite well into the overall approach being taken by the ENTRUST project and has helped the authors to gain a deeper understanding of how the political system deals with the complexity that is ingrained in the energy transition. Also, how the frameworks within which socio-political institutions and policy paradigms operate and influence the direction and speed of the transition is explored. As key influencers in the energy transition, institutions play a key role in governing the behaviours on multiple levels, from individuals to the communities they participate in. The term "institution" is somewhat amorphous in its usage. It has been commonly used to describe both the formal entities setup to regulate people (e.g., supranational and national governments and the public services they provide) and the more informal practices associated with individual and group customs or behavioural patterns that have been valorised by societies over a period of time (e.g., national cuisines, and adherence to specific religious or secular festivals). This relational perspective on how social order is both created and maintained is important as it helps us to gain a better understanding of the factors that contribute to the strengths and weaknesses of the various policies being implemented across the EU to promote the energy transition. In taking this approach the strengths and challenges to energy transition are, in turn, highlighted in each country. Important national energy systems’ characteristics are also discussed, such as energy security, climate change, and the resultant threats to human health and ecosystems. In the first part of the deliverable, a theoretical introduction of the different concepts developed for this task are presented, followed by a general overview of EU energy policy and the detailed assessment of the six Member States’ energy systems. Key Performance Indicators, along with an assessment of the factors contributing to specific successful outcomes are used to reveal the differences between the six countries.