We spend about 90% of our lives inside building, and much of our behaviour is shaped by this experience of the built environment. We live in houses; work in factories, hospitals, offices; study in schools and colleges; shop in supermarkets; dine in restaurants; take holidays in hotels, and so on. Buildings provide for our basic needs, giving protection against the elements, shelter and security. They are functional spaces allowing us to perform work, learn, and play, irrespective of prevailing climate conditions. Yet they can also affect our feelings, e.g. marvelling at the grandeur of St. Paul’s. They can signify extensions of ourselves either as individuals, e.g. how we decorate and maintain our homes, or as organisations, e.g. the formal grandeur of the Houses of Parliament creates an image unmistakably British. Buildings are an integral part of our cultural heritage and future development. Yet it is not the “bricks and mortar” of buildings that interest environmental psychologists, but the way in which any physical setting can facilitate or inhibit those behaviours which give meaning to the setting and which make it either a success or a failure.