My main interests are in Gentzen systems for various logics, particularly modal logics and temporal logics. Currently I am working on the intricacies of Display Logic and how to obtain Gentzen systems for hybrid logics like intuitionistic modal logic. With Jeremy Dawson, I am working on formalising proofs of weak and strong normalisation for various calculi in the logical framework Isabelle. With Vaughan Coulthard, Jen Davoren and Thomas Moor I am working on inventing bi-modal tense logics with applications in hybrid systems. I am also interested in software engineering and security aspects of Java applications, particularly for JavaCards.