In recent years, there has been an increased interest in how people actually experience their interactions with digital technology, and more research is now addressing issues going beyond the instrumental. This approach to understanding digital technology is often referred to as user experience. In this thesis, I take the perspective of user experience, and investigate how ambiguity can be used as a resource for making the user start a reflective activity. In order to do this, a review of theories and concepts in the emerging field of user experience is conducted. The use of ambiguity as a resource for design is discussed, and a set of concepts for addressing user experience is presented. My main understanding of user experience is derived from John McCarthy and Peter Wright’s framework for understanding technology as experience (McCarthy and Wright 2004). They see user experience as a situated, creative process of making sense. The empirical data is derived from my participation in an experimental research project conducted at the University of Oslo. In this project, an exhibition mediating the process of reconstructing an old Viking boat was designed and implemented. The project’s main aim was to explore the potential of using digital technology as a mean to communicate cultural heritage to young people. At the end of the design process, a group of teenagers was invited to the exhibition, and their behaviours and use of technology was thoroughly studied. I investigated both the design and use of the exhibition. My findings make evident how the exhibition used ambiguity in order to make the visitors start a reflective activity, and point out two main categories of situations where the teenagers expressed uncertainty and doubt. Moreover, I use what McCarthy and Wright call the six processes of sense making and their underlying pragmatic philosophy in order to further deepen our understanding of how ambiguity can used as a resource for design.