I am VP and Engineering Fellow at Google, where I lead work on natural-language understanding and machine learning. My previous positions include chair of the Computer and Information Science department of the University of Pennsylvania, head of the Machine Learning and Information Retrieval department at AT&T Labs, and research and management positions at SRI International. I received a Ph.D. in Artificial Intelligence from the University of Edinburgh in 1982, and I have over 120 research publications on computational linguistics, machine learning, bioinformatics, speech recognition, and logic programming, as well as several patents. I was elected AAAI Fellow in 1991 for contributions to computational linguistics and logic programming, and ACM Fellow in 2010 for contributions to machine-learning models of natural language and biological sequences. I was president of the Association for Computational Linguistics in 1993.