In order to facilitate data sharing and unambiguous interpretation of data between different researchers, it is imperative to share a common vocabulary. CUAHSI maintains a community-driven, WDC staff-moderated set of controlled vocabularies for the Observations Data Model (ODM). The ODM Master Controlled Vocabulary Registry is the website for data managers to request new or updated items to this controlled vocabulary and users can also view the current master controlled vocabulary terms. These items are stored in a master database and web services are implemented on top of it in order to enable access. The web services broadcast the terms within the master repository in XML format.Data publishers who host their data with CUAHSI do not need to worry about updating their databases as this is a service that the WDC staff provides.. However, data managers who maintain their own server can use the ODM Tools application to compare their local controlled vocabulary with the master repository and download any updated or added terms. ODM Tools gets the controlled vocabulary terms from the local database, accesses the ODM Controlled Vocabulary web services and automatically parses the XML messages that are returned, and then presents a tabular, side-by-side comparison of local and master terms. Users can then compare the terms in their local database with those in the master list and add any new or updated terms to their local database.