David Gray's main research interests are in the areas of Security, Internet Technologies and Formal Methods. In particular, Dr. Gray is interested in Public Key Infrastructures (PKIs), the application of formal techniques to the specification and analysis of PKIs and related security protocols, and Secure Location-Based Services on the Internet.

Dr. Gray was principal investigator for the Enterprise Ireland funded project, IMPROVE, that studied the application of formal methods to security protocols that use PKIs. He is currently principal investigator on the Enterprise Ireland funded project "A Secure Infrastructure for Location-Dependent Services on the Internet". The aim of this project is to design an infrastructure that will allow a user's location information to be made available, with appropriate security applied, to Internet-based applications.