The European Diamond Capacity Hub (EDCH) is an OPERAS programme designed to strengthen and coordinate community-led Diamond Open Access (OA) efforts and actors across Europe. At the heart of EDCH’s mission is the creation of a high-quality, aligned, and sustainable Diamond OA infrastructure. Diamond OA offers an equitable, nonprofit model of scholarly publishing that supports multilingualism and bibliodiversity. However, its growth, visibility and sustainability depend on a robust infrastructure, secured funding and effective coordination across disciplines and geographical borders. Building on the outputs of the highly successful and influential DIAMAS and CRAFT-OA projects, the EDCH was established as a central hub that coordinates and provides services, tools, and guidelines to European communities involved in Diamond OA. It supports National Capacity Centres, publishers, and service providers at different levels of maturity and involvement with Diamond OA, by offering quality assurance frameworks, training and capacity-building resources. The EDCH services and tools portfolio includes the: Diamond Discovery Hub (DDH): A comprehensive registry of European Diamond OA journals that meet operational criteria, enhancing their visibility and discoverability among authors, institutions, and funders. Diamond Open Access Standard (DOAS) & Self-Assessment Tools: A quality assurance framework and benchmarking instruments that support publishers and service providers in assessing and improving both their operational practices and long-term sustainability. Resources & Guidelines: A curated collection of practical guidance, good practices, and instructional materials that help organisations transition to, implement, and optimise Diamond OA publishing. Registry & Forum: Virtual spaces where publishers, service providers, tools and technology experts, and capacity centres can connect, collaborate, and present their work strengthening community ties and knowledge exchange. Training Platform: An online environment offering skill-building modules, curricula, and training resources tailored to foundational and advanced aspects of Diamond OA publishing, including financial sustainability, editorial workflows, and technical competencies. Publishing Tools: A forthcoming set of software tools and integrations designed to enhance publishing workflows improving interoperability, technical efficiency, and adoption of standards across platforms. This poster presents an overview of the EDCH services and infrastructure, and highlights opportunities for organisations, libraries, publishers, and infrastructure providers to engage with and benefit from the European Diamond OA ecosystem.