My research is centred around artificial intelligence, in particular the areas of automated planning, knowledge representation and reasoning, and cognitive robotics. I am interested in the problem of reasoning about knowledge and action, especially under conditions of incomplete information and uncertainty, with a focus on formal modelling and the development of tractable reasoning mechanisms for planning and high-level robot control. My research is also concerned with the construction of practical planning systems, with deployments on robot platforms and applications to human-robot interaction, natural language dialogue, and social robotics.