I am a professor in the research group DistriNet (Distributed Systems and Computer Networks) at the Computer Science department of the Katholieke Universiteit Leuven. Since 1999, my main research interests are in the field of software security, where I focus on the development of high-assurance techniques to deal with implementation-level software vulnerabilities and bugs, including techniques such as software verification, run-time monitoring, type systems and language based security. These techniques are relevant for many types of software systems, including web applications, embedded software, mobile applications and so forth. In the period 1992-1998, I have worked on foundations of semantic modeling. In particular, I studied categorical approaches to semantic modeling. Using sketches as a specification formalism, I investigated the problem of deciding semantic equivalence of specifications.