Construction is fundamentally an anti-ecological activity, involving the deployment of vast quantities of materials, energy, carbon and labour. So we figure that the most useful thing we as architects can do is to make sure that the embodied energy of the buildings we construct is used for the longest possible time, by designing buildings that are flexible, clever, robust and beautiful. Equally, if we can bring back into productive new uses buildings whose current utility is at an end, we are similarly doing our bit for the planet. The projects shown here take buildings whose possibilities for the future are often under-appreciated, and demonstrate how reuse is not only more sustainable but usually also more economical too. As Jane Jacobs has said, ‘New ideas need old buildings.’