This SPARC Europe's webinar brought together voices from Croatia, France, Finland, the Netherlands, and Spain. Experts from these countries talked us through their initial influences and motivations for establishing national and regional platforms. They shared their perspectives on building and running national and regional OA publishing platforms and spoke about how they had evolved over time through presentations. A panel discussion touched upon challenges they had encountered and shared the lessons they had learned when joining forces and collaborating. They also talked about their future plans to increase collaboration be this locally or internationally. This webinar focused on the following topics: What community-governed, publicly-funded not-for-profit national and regional OA publishing platforms are already set up in Europe Which opportunities and challenges come with setting up a national or regional OA platform and collaborating with smaller publishers What the best practices for national and regional OA platforms are, as seen by experienced experts in the field You can see the recording here: https://youtu.be/dtGIl3us7G8