As the offshore renewable energy (ORE) sector matures in Europe, the integration of the technologies in coastal territories, already largely exploited by a multitude of human activities, is a challenge in itself (Gusatu et al. 2020). This integration depends in part, on the support of the ORE projects by local communities. Although the research on the perception of ORE identifies attitudes that are globally positive to the development of ORE (Oiry 2015, Sokoloski et al. 2018), oppositions persists that can have a strong impact on the ORE planification. Several studies have already identified recommendations to better engage with local communities and facilitate the ORE planning (e.g., Bush and Hoagland 2016, Dwyer and Bidwell 2019). The sharing of scientific information around projects is notably very important (Joalland and Mahieu 2023), and the way public consultations are conducted and local communities are involved greatly influence the emergence of controversies and their evolution (Wahlund and Palm 2022). Although these recommendations are known, they are not always followed (Cronin et al. 2021). In addition, the requirements for, and the type of public engagement promoters undertake, in order to deliver their “license to operate” and bring forward ocean energy projects, varies greatly from one European country to another (Burkhard and Gee 2012, Evrard and Pasquier 2019). Long term planning to meet European decarbonization commitments needs to be supported by a better understanding of engagement processes and public perceptions, together with the development of tools and recommendations to support the coexistence of ORE with a wide range of stakeholders. Our contribution provides feedback based on surveys and interviews with ORE developers and regulators in Europe. The analysis of very contrasting situations allows us to develop a critical view of challenges and practices over ORE project’s integration in coastal territories. The study is focused on a dual dimension of the ORE integration. First, we collect the perception of developers and regulators about bottlenecks in both legal and political frameworks at the EU scale and in several European countries. In relation with this regulatory framework perspective, we then identify the practices of developers to engage with local communities and evaluate their impact on ORE projects. The resulting outputs offers a set of lessons learn from the projects, to improve political and democratic processes around ORE development and propose an engagement of local communities at the service of the planification of offshore energies.