This iterative working paper presents a set of high-level interactive components necessary for a functioning FAIR ecosystem. Operational repositories, and other (meta)data related services are supported by common reference information managed in registries, and by evaluation processes consisting of standards and assessment methods. Findable, Accessible, Interoperable and Reusable digital objects (data and metadata) are a necessary input to, and output from, ecosystems that integrate (one provider serves many) or federate (many providers interoperate) services. Users of all kinds must be empowered to find and access (meta)data that supports interoperability and reuse. All ecosystem actors depend on machine and human-mediated evaluation of digital objects’ FAIRness.