London: Tomorrow's city?
As we head towards a new era of urbanisation - half of the world's population will live in cities by 2050 - the race is on to make our cities fit for purpose.
Technology is playing a bigger role in helping to make city life run more smoothly, from networks of sensors that offer information about how traffic is flowing or where water pipes are leaking to apps designed to help citizens get the most out of their city.
London is one of the key cities at the forefront of this smart thinking, as Jane Wakefield explains.