This chapter discusses the concept of sensitive environments. Sensitive environments are essentially spatial and public areas like streets or school that are provided with an intelligent infrastructure that collects sensory information of users while they move and interact. Such sensitive environments offer researchers an environment which enables them to automatically collect lots of data. However, when data collection takes place through a sensitive environment instead of by interviews, questionnaires and structured observations, it consequently changes the nature of social research and imposes new types of questions: How to design the environment to fit the research questions. How do we deal with huge datasets in a sensible way? How can we interpret data that might be incomplete or uncertain in a meaningful and useful way? In the remainder of this work, we discus the use of sensitive environments as a tool for social research embedded within everyday life.