Yijun Yu is a Senior Lecturer in the Department of Computing and Communications at The Open University. He is a member of the IEEE Computer Society and the British Computer Society. His research has focused on software systems: changes at development time; changes at runtime; changes among viewpoints; changes to stakeholders; changes to the attack/defense; changes to the interests disclosure; and the bidirectional synchronizations of various kinds of changes. He is currently working on a European Union project, SecureChange, analyzing security requirements for air traffic control.