The Open Science Persistent Demonstrator (OSPD) is a long-term inter-agency initiative aiming to enable and communicate reproducible Earth Science across global communities of users and amplify inter-agency Earth Observation mission data, tools, and infrastructures. This talk will highlight the status and roadmap of the initiative (kicked off in 2023) and will provide an outlook on the first pilot activities of the demonstrator, as well as opportunities for participation for the FOSS4G community. In the scope of this activity, ESA, NASA and OGC work together on the development of a long-term Open Science framework (e.g., a permanent open science demonstrator) in which participating organisations provide data, tools, and infrastructure in a coordinated approach, building on existing investments where appropriate. In the frame of this activity, the OGC supports the Open-Source and Open Science Community by developing a persistent demonstrator that makes Open Science more tangible to a bigger audience, helps in exploring new forms of communication of scientific results to stakeholders, and helps develop the necessary standards to ensure the highest levels of interoperability across participating organizations. At the same time, it makes Earth Observation results available to other disciplines and communities, creates attention beyond the Earth Observation community, and directly impacts decision makers and political agendas. The goal here is to demonstrate interoperable, collaborative research that allows reuse of existing components. These other resources are either offered as part of emerging Open Science Environments or in the form of either directly accessible “cloud-native” data/functions or by means of Web APIs. To reach this goal, it is essential to empower communities of practice to share FAIR (Findable, Accessible, Interoperable, Reusable) descriptions of their resources and capabilities. To allow this system to scale, it is crucial to avoid infinite combinations of community and application specific metadata, functions, data and products. One focus is the facilitation of direct participation of the scientific community as the primary users of this framework, and of the open-source for geospatial community as essential contributors to the activity. To handle modelling complexity, OGC, NASA and ESA will define manageable processes and best practices for communities conducting geoscience research in multiple domains using heterogeneous data and tools on a distributed infrastructure. These agreements will include, but not limited to, standards, vocabularies, and ontologies for data and workflows and develop community-wide open source science mechanisms, modeling considerations and design patterns.