Task-based User Interface Design

Preface This thesis could not have been written without the help and inspiration of many people around me. At the Vrije Universiteit, I was in an interesting environment with many different ideas. I want to thank Gerrit van der Veer, Anton Eliëns and Hans van Vliet for their enthusiasm and how they enriched my research by showing me their perspectives. Thanks to Gerrit for introducing me to the " world of Human Computer Interaction ". I very much enjoyed our collaboration where we had different approaches to a common interest. Thanks to Anton for " convincing " me to do a Ph.D. in the first place and for showing me the use of several interesting techniques during the development of my tool EUTERPE. I also want to thank many other people who supported me throughout the last years. A big part of that was due to Bastiaan Schönhage, by being a friend and roommate for many years. We sure had a lot of fun in between the " serious " work. It was very good to have someone like him to discuss " raw " ideas and to keep me from " overdoing " it. During the last months, we were both writing our dissertation which definitely helped me to keep up the spirit and finish it in time. In addition, thanks to my direct colleagues Nico Lassing, Jacco van Ossenbruggen, Frank Niessink and Jaap Gordijn. During a working day, it is also important to relax and have pointless discussions, for example during lunch when Arno Bakker and Gerco Ballintijn used to join us. Thanks to Hallvard Traetteberg for his work on the patterns. During the development of the patterns he was my best reviewer and contributor. Without his help I would not have developed them so fast. Joerka Deen also proved to be a good discussion partner, always emphasizing the more " philosophical " side of patterns. And of course, many thanks to my parents, my sister and Merche for all their support and love during these years.