He is author of several books on object oriented concepts, including a chapter on the Object-Oriented Language Paradigm in the upcoming "Computer Science and Engineering Handbook" edited by Allen B. Tucker (CRC Press, 2003). He is an active researcher in the area of object-oriented concepts, and their application to programming, user interfaces, databases, simulation and software engineering. He has presented numerous successful and highly rated tutorials at major conferences (OOPSLA, ECOOP, TOOLS).