Our Erasmus+ Project ENSITE (ENvironmental Socio-Scientific Issues in Initial Teacher Education) supports the development of future science and maths (from now on referred to as science) teachers’ environmental citizenship and related teaching competences.We face severe global environmental challenges such as deforestation and plastic waste. Europe’s society needs to acknowledge these challenges and accept their role in supporting sustainable development. Our educational systems have to fulfil the obligation to enable citizens to do so. Science education, in particular, must equip them with the ability to find adequate technological solutions.ENSITE supports this endeavour. Research proposes the engagement of socio-scientific issues (SSI) as one promising path to developing environmental citizenship competences. However, science teachers graduating from higher education (HE) institutions are not prepared to teach SSI, because they not only require teaching “scientific facts” but also involve controversial information, complex data sets and ethical, social, economic or cultural motives. Such aspects are rarely covered in initial teacher education (ITE).We aim at improving HE by including environmental SSI in science ITE. To this end we will develop an innovative approach to support teachers in (1) developing competences in dealing with environmental SSI (“Learning”) and (B) acquiring teaching skills to supporting their future students at school in becoming responsible citizens (“Teaching”) themselves.ENSITE consists of 11 HE teams from institutions across Europe comprising experts in science education (research and practice), environmental issues, pedagogical concepts to acquire transversal and forward-looking skills (e.g. critical thinking, creativity, reasoning, reflection), students’ mobility, diversity in science courses/classrooms and large scale dissemination. All partners acknowledged that their educational science courses rarely cover citizenship education and see huge potential with regard to benefits for them and their students.We decided on a thoroughly elaborated range of activities to produce purposeful results.Our research activities cover the development of 13 teaching modules on environmental SSIs for future science teachers. These intellectual outputs (IOs) cover subject knowledge on SSIs (definitions, topic areas, relevance, etc.) and how to deal with them, implications for learning/teaching processes, pedagogical concepts to design lessons, and the role of teachers’ background (beliefs, cultural, etc.) which affects teaching SSIs.In order to ensure highest quality and a convincing red thread relating to our overall topic (environmental citizenship education), each research activity follows a clear methodology: In our iterative design process, each development phase is followed by a review and pilot, optimisation loop and, finally, production. Every partner has precisely defined responsibilities. Project meetings will be organized to support internal communication.We perform several pilot activities validating our IOs at partner HEI and paving the way for long-term implementation. We use feedback from participating teaching staff and students to improve our IOs (content, user-friendliness, media format, impact etc.).We will also disseminate our results in three subsequent summer schools. Thus, in every project year we will reach out to future science teachers across Europe. We will present our IOs, engage students in a variety of innovative activities and stimulate inter-cultural and social experiences. Feedback collected during our summer schools will be used to further improve our materials.We organize (national and international) multiplier events to promote the project among relevant educational stakeholders, initializing dialogue on the matters at hand and substantiate our findings, as well as boost sustainable dissemination and exploitation.We plan several targeted European-wide and national communication, dissemination and exploitation activities, such as establishing a web portal, pursuing a flexible and modern social media strategy or scientifically present our research findings.We expect ENSITE to boost innovation in HE and more particularly science ITE across Europe. This will lead to a substantially higher number of HE educators with a versatile range of scientific, transversal skills, citizenship competences and related teaching competences. In the longer term, this contributes to a widespread shared awareness of social and environmental responsibility. Our open-access materials will support Europe’s science teaching staff to benefit beyond project duration. Our materials will particularly allow each partner HEI to strengthen their trans-national collaboration, implement innovative approaches in their science ITE programmes and facilitate institutional change, raise their reputation, and actively contribute to Europe’s smart, sustainable and inclusive growth.