The I-ADOPT WG will focus on creating a community-agreed framework for representing observable properties by bringing together groups that have been working on developing terminologies to accurately encode what was measured, observed, derived, or computed. The consensus building will be informed by reviewing current practices and by a set of use cases, which will be used to define the requirements and to test and refine the common framework iteratively. Much like a generic blueprint, this framework will be a basis upon which terminology developers can formulate local, but globally aligned, design patterns. With these, they may leverage their local “materials” in a multi-pronged attempt to represent complex properties observed across the environmental sciences (from marine to terrestrial ecosystems, as well as biodiversity, atmospheric, and Earth sciences). The WG will then seek to synthesize these approaches into global best practice recommendations. Furthermore, it will help mediate between generic observation standards (SSNO, SensorML, ..) and current community-led resources, fostering harmonized implementations. Through this effort, FAIRer observable property terminologies will be created, the global effectiveness of tools operating upon them will be improved and their impact increased. The WG will thus strengthen existing collaborations and build new connections between terminology developers and providers, disciplinary experts, and representatives of scientific data user groups.