Abstract: As computers are increasingly woven into the fabric of everyday life, interaction design may have to change - from creating only fast and efficient tools to be used during a limited time in specific situations, to creating technology that surrounds us and therefore is a part of our activities for long periods of time. We present slow technology: a design agenda for technology aimed at reflection and moments of mental rest rather than efficiency in performance. The aim of this paper is to develop a design philosophy for slow technology, to discuss general design principles and to revisit some basic issues in interaction design from a more philosophical point of view. We discuss examples of soniture and informative art as instances of slow technology and as examples on how the design principles can be applied in practice.