RangeX is anchored in a unique existing database of plant distribution and community composition collected from standardized, temporally repeated surveys across elevation gradients from 24 mountain regions around the world (c. 100,000 georeferenced occurrences of native and non-native plants) by the Mountain Invasion Research Network (MIREN; www.mountaininvasions.org). MIREN has studied plant redistribution in mountains since 2006, including the spread of non-native species and range expansions of native species with climate warming. A relational database will host RangeX data, including the complete MIREN survey and associated plant trait and microclimate data, to facilitate data sharing within the project and to manage data requests and open access.