 He is well known for his work on computer security and on programming languages, including his paper (with Michael Burrows and Roger Needham) on the "Burrows-Abadi-Needham logic" for analyzing authentication protocols, and his book (with Luca Cardelli) "A Theory of Objects", laying out formal calculi for the semantics of object-oriented programming languages.He is a 2008 Fellow of the Association for Computing Machinery.In 2011, he was a temporary professor at the Collège de France in Paris, teaching computer security.