Peter F. Patel-Schneider is a Member of Technical Staff in Bell Labs Research. He received his Ph. D. from the University of Toronto in 1987. Peter was a member of the AI Principles Research Department at AT&T Bell Laboratories from 1988 to 1995, and went to AT&T Labs - Research when AT&T split up. In August 1997 he rejoined Bell Labs. From 1983 to 1988 he worked in the AI research group at Fairchild and Schlumberger. Peter has taught courses at both the University of Toronto and Rutgers University. Peter's research interests center on the properties and use of Description Logics. He has designed and implemented large sections of CLASSIC, a Description Logic-based Knowledge Representation system. He designed and implemented DLP, a heavily-optimized prover for expressive Description Logics and propositional modal logics. He has performed extensive empirical evaluation of DLP and other provers for Description Logics and propositional modal logics. He developed much of the W3C OWL Web Ontology Language, and its predecessor, DAML+OIL. He is currently building and testing provers for OWL and related languages. Peter is also interested in rule-based systems, including more-standard systems derived from OPS as well as newer formalisms such as R++. He designed many of the techniques used in R++ and the R++ translator, and wrote the first several prototype implementations of the R++ translator.