Two aspects of our research concern the application of formal methods in human-computer interaction. The first aspect is the modelling and analysis of interactive devices with a particular emphasis on the user device dyad. The second is the modelling and analysis of ubiquitous systems where there are many users, one might say crowds of users.The common thread of both is to articulate and prove properties of interactive systems, to explore interactive behaviour as it influences the user, with a particular emphasis on interaction failure. The goal is to develop systematic techniques that can be packaged in such a way that they can be used effectively by developers. This “whitepaper” will briefly describe the two approaches and their potential value as well as their limitations and development opportunities
