The word 'habitat' refers to the environment within which we live. For us today, the built environment is the most immediate habitat. It is a habitat that we build and shape in the very process of living in it. In turn the built environment also shapes our lives in many direct and indirect ways. This Concentration focuses attention on the built (and lived) environment and its different components, how they are shaped through a variety of social processes, and how it impacts everyday life. The term 'built environment' here includes the system of urban spaces, or 'hardware', we inhabit- homes, streets, open spaces, railway stations, beaches, urban forests etc. The way goals of justice and efficiency are realized in people's experience of the built environment will be an important thread running through the course.