Although City Cars can work quite nicely as privately owned vehicles, they provide the greatest sustainability benefits when they are integrated into citywide, intelligently coordinated, shared-use mobility systems. The idea is to locate stacks of City Cars at major origin and destination points, such as transit stops, airports, hotels, apartment buildings, supermarkets, convenience stores, universities, hospitals, and so on. You just swipe a credit card, drive a vehicle away from the front of the stack, and return it to the rear of another stack at your final destination. From the user’s perspective, it’s like having valet parking everywhere. Image: ©

For too long, too much of the discussion about urban mobility and its relationship to sustainability has been locked into an increasingly sterile debate between proponents of public transit and advocates of the automobile. Both sides ignore some inconvenient truths. Image: © Franco Vairani/MIT Smart Cities Project Six to 8 stacked City Cars can fit into one traditional parking space. When located at major origin and destination spots, such as transit stations, they can carry people the last mile to their final destinations. Transit enthusiasts point out the inherent efficiencies of high-capacity public-transportation networks, but often neglect to mention that,