Provide astronomers with simple, efficient and rapid means of accessing the reference data (bibliography, catalogues, object identifiers, images, spectra, time series,...) necessary for their research". Since its creation in the early 1970s, the Strasbourg astronomical Data Centre (CDS) has addressed this challenge. The context and technologies have evolved from post mail to touchscreen devices, but the challenge remains: identify, collect, homogenize, describe data, and then redistribute it so that the knowledge can be re-used. What is called nowadays: the FAIR principles. At the heart of this challenge: the data interoperability. Standards, data serialization, metadata, dictionaries, tools, languages, semantics... Based on our experience at CDS, we will try to identify the good, but also the bad, of the various interoperability solutions that have marked the evolution of CDS: those that work, those that failed. We will try to draw some lessons from the past experiences, and try to consider what the interoperability might enable for future astronomical projects.