The KR&R group investigates modelling and representation of different forms of knowledge and reasoning, as found in a large variety of AI systems. We have an interest in both applications and theory. We study theoretical properties of knowledge representation and reasoning formalisms, but are also involved in developing practical knowledge-based systems. We have been very active in developments around the Semantic Web. We test and apply our insights in medical applications and in e-science (pharmacology, social science, humanities).