Federated metadata search for the polar regions is dependent on the data centres that host polar-relevant data being able to present discovery metadata in a common way. The POLDER working group is developing a best practice guidance for the implementation of schema.org as a potentially light weight discovery metadata standard serving in particular the long tail data. The polar guidance contributes to and draws on similar efforts in allied science communities. This session will progress the development of that best practice documentation as well as inform the development of the pilot federated search tool that is currently being supported by the World Data System.