Diamond Open Access (OA) is a publishing model that eliminates fees for both authors and readers, promoting equitable access to scholarly content. In Europe, Diamond OA is gaining attention as a sustainable approach to Open Access publishing. Various initiatives support its growth, including EC-funded projects like CRAFT-OA and DIAMAS, national and institutional commitments, and international efforts such as the Global Diamond Open Access Alliance launched by UNESCO. Despite its potential, Diamond OA faces challenges like under-funding, technological gaps, and undervaluation in research assessments. The CRAFT-OA project and OpenAIRE, a non-profit European partnership, are developing services to advance Diamond OA publishers technologically. These include: Open Journal Systems (OJS) Plugin for OpenAIRE Guidelines: This plugin helps integrate diamond journals into the OpenAIRE Graph, ensuring compliance with metadata standards and improving discoverability and interoperability. OJS Plugin for the OpenAIRE Broker: The Broker notifies journals about enrichments that OpenAIRE added to their metadata records - such as funding information or related datasets - enhancing the quality and completeness of bibliographic records. MONITOR Dashboard for Diamond OA Publishers: This platform offers analytics and reporting capabilities, tracking key performance indicators like citation metrics, FAIRness indicators, impact on the United Nations’ Sustainable Development Goals. The MONITOR dashboard is also available to research-performing organizations like universities and university alliances. Combined with the OpenAIRE CONNECT service, RPOs enhance the visibility and discoverability of their various research outputs, including theses, reports, datasets, and software. These innovations collectively enhance the visibility, robustness, and inclusivity of the Diamond OA and grey literature publishing landscape. References The CRAFT-OA project (Creating a Robust Accessible Federated Technology for Open Access), https://www.craft-oa.eu/ OpenAIRE, www.openaire.eu OJS Plugin for OpenAIRE Guidelines: https://github.com/munipress/openAIREstandard Gomola, R., Dvořáková, M., & Růžička, M. (2024). CRAFT-OA Deliverable 6.1_OJS Connector for OpenAIRE Research Graph (Draft). Zenodo. https://doi.org/10.5281/zenodo.12633203