Martin Kaltenbrunner is Professor at the Interface Culture Lab, University of Art and Industrial Design in Linz. His research concentrates on tangible user interfaces and the development of novel human computer interaction concepts within open tools for creative production. As co-founder of Reactable Systems he had been mainly working on the interaction design of the Reactable - an electronic musical instrument with a tangible user interface. He is author of the open source tangible interaction framework reacTIVision and the related TUIO protocol, which have been widely adopted for the realization of tangible tabletop applications.