Detailed knowledge of digital representation formats is necessary to interpret properly the full information content of otherwise opaque content streams. The Digital Library Federation (DLF) has sponsored preliminary investigations towards establishing a Global Digital Format Registry (GDFR) that will provide persistent, unambiguous bindings between public identifiers for digital formats and the significant syntactic and semantic properties of those formats. These properties are an important component of the representation information necessary for effective digital preservation. The existence of a GDFR should prove to be of great utility to archives, libraries, digital repositories, and other organizations and individuals interested in the long-term viability of digital information.