Metadata standards at Indiana University are well-established for many of our digital library collections. These standards have been expressed, for the most part, using XML - it's easy to store, easy to read, easy to update, and easy to share. Newer forms of digital library technology, however, are expanding/enhancing the way that data is stored with and about digital objects, using the Resource Description Framework (RDF) to construct relationships, descriptions, and digital objects that are more semantically connected to the web. This new way of standardizing metadata has presented many challenges: introducing a new model midway through projects, migrating content from older models to RDF models, and figuring out in general what it means to use an RDF model for digital library collections. This talk will discuss what has happened in the IU digital libraries with RDF to-date and the challenges and opportunities from this work.