The complexities of large cities present a myriad of challenges as much as developing the car and technology itself, but there have already been early discussions with Singapore and Hong Kong to test drive the cars and system on a small scale.

CNN: Reinventing the wheel

Lower start-up costs and less strict worker protection make it easier for innovative entrepreneurs in America to experiment on a small scale (hence the smaller size of new firms), to test the markets and to expand.

ECONOMIST: Economics focus