Vaccination is an increasing priority at global, European, and national levels. Given stagnating vaccination coverage across Europe, fueled in part by growing vaccine hesitancy and the specific challenges posed by the COVID-19 pandemic, targeted action through a 'whole of society' approach should be taken to increase vaccine uptake and contribute to the 2018 Council Recommendation on vaccination. Building on existing initiatives and learnings, the IMMUNION project (Improving IMMunisation cooperation in the European UNION) will add value to EU and national initiatives - particularly the Coalition for Vaccination. IMMUNION's consortium partners represent five Coalition for Vaccination members, four national public health actors, one university and two media and communications firms. This balanced partnership will cooperate to increase stakeholder collaboration to address issues of access to accurate information about vaccination and to improve education and training opportunities for health professionals and students. Project activities are tied directly to the project's general and specific objectives, with the ultimate aim to support the Coalition for Vaccination. Activities are spread across six complementary and inter-linking work packages that are joined together by a focus on effective communication - both within the health sector and to wider groups in society. Activities include the development of a dedicated Coalition for Vaccination website with integration to the existing SEKI Platform, a Training-of-Trainers Workshop, developing National Toolboxes of vaccination communication best practices, and improving the visibility of the Coalition for Vaccination. Expected outcomes include increased awareness and use of validated training materials, increased ability for health professionals and students to communicate about vaccines, enhanced media reporting on vaccination, and improved overall equity in vaccination for populations with lower vaccine coverage.