He received his PhD in information science at Cornell University where he held numerous research positions and subsequently served on the faculty of the Information Science Department. The overarching theme of his research for the past two decades is interoperability of information systems, spanning the full spectrum of technical and human components that are critical to create networked information systems that really work. Although the results of this research apply across a variety of information contexts, the primary thread of his research explores information systems to support scholarship and knowledge production. The results of this research career are manifested in a number of widely used applications, protocols, and standards in areas such as metadata harvesting, ontology definition, and repository architecture.