Starting afresh presents opportunities to create settlements which respond to the technical, social, environmental and aesthetic ideas of our own times. We wish, for example, to have settlements which are sustainable, good for parents who have jobs, good for old folk who wish to live near their children, good for families who want both community and privacy. The classic twentieth century 'single' housing area does not possess these characteristics. A single use, housing, causes long journeys to work, shops and schools. A single dwelling size, for 2.4 children, causes families to move as they grow and change. A single transport mode, the car, causes low residential densities and excessive use of non-renewable energy. So we need models for new settlements. This requires investment in innovation, as do new aeroplanes and computers.