On 17 September 2025, the AARC-TREE project held a dedicated workshop to gather community input on the upcoming release of the Compendium of Best Practices and Recommendations. The event, hosted at CERN and co-located with the OSCARS Composability Workshop, focused on refining the Compendium’s structure, scope, and usability for diverse audiences.

Participants discussed how the Compendium can best support AAI adoption across research infrastructures, stressing the need for clear definitions, consistent terminology, and practical guidance. Four use cases helped fine-tune the AARC Guidelines, outlined implementation challenges and explored how the Compendium would be instrumental in facilitating wider adoption, particularly by Research Infrastructures. 

Key feedback included:

• Ensuring accessibility for both technical experts and non-specialist audiences, including funders and policymakers.
• Providing stronger guidance on best practices and avoiding unnecessary reinvention of solutions.
• Clarifying the role of federated solutions compared to commercial alternatives.
• Addressing sustainability, governance, and funding challenges to maintain AAI tools beyond project lifetimes.
• Highlighting real-world use cases and challenges such as guest identities, federated SSH (Secure Shell), and Trusted Research Environments.

The workshop also showcased technical pilots and the automated validator suite, designed to assess compliance with AARC guidelines, and explored future directions such as OpenID Federation and interoperability with EOSC AAI.

Looking ahead, the project will continue refining the Compendium, with milestones including the initial version release in October 2025, and the official launch of the Compendium in January 2026.

The workshop reaffirmed AARC-TREE’s role in championing federated access, supporting communities at different maturity levels, and ensuring sustainable, interoperable AAI solutions for the European research landscape.