We have built a configurable infrastructure to protect users' dynamic levels of�privacy in a pervasive sensor network. Our system is based around a badge that can alert the user to the presence of participating sensor networks, plus emit an RF beacon with which the network can gauge the level of privacy desired. Badges either periodically emit an "opt out" signal, blocking sensing within their RF (and sensor perceptual) range, or allow the users' desired level of privacy to be preconfigured online. This privacy level depends on user location, and can eliminate or "blur" the data and calculated features available from various sensors and sensor nodes. The privacy level can also be dependent on the status of the client browsing the sensor network�the badge user can assign different levels of privacy to different groups of people.