In our research, we have been concerned with the question of how to make relevant features of security situations visible to users in order to allow them to make informed decisions regarding potential privacy and security problems, as well as regarding potential implications of their actions. To this end, we have designed technical infrastructures that make visible the configurations, activities, and implications of available security mechanisms. This thus allows users to make informed choices and take coordinated and appropriate actions when necessary. This work differs from the more traditional security usability work in that our focus is not only on the usability of security mechanism (e.g., the ease-of-use of an access control interface), but how security can manifest itself as part of people’s interactions with and through information systems (i.e., how people experience and interpret privacy and security situations, and are enabled or constrained by existing technological mech...