This paper presents findings from initial fieldwork studies of sustainable energy community development methodologies in two islands in Denmark and one rural village in Ireland. The main goals of this study were to determine the enablers and barriers to their successful development and to assess the successful elements of these previously implemented sustainable energy community development methodologies. The study involved extensive semi-structured interviews with the managers of the sustainable energy community projects and comprehensive site visits of each project. The evidence presented in this paper indicates that social barriers are interconnected and often reinforce each other. This article suggests that a comprehensive understanding of how barriers can be transformed into enablers supports the successful development of sustainable energy communities at local level in Europe. The findings in this research indicate that although each of the sustainable energy communities studied did not have any specific implementation framework developed for their projects, many of the successful tools and methodologies used across all communities were similar. The significant contribution of this work is the illumination of key factors influencing the successful development of sustainable energy communities in Ireland and Europe.