"In China, most people don't take personal responsibility for the bad air," notes Ogilvy/Beijing CD Doug Schiff. "But since Beijing has over three million cars on the road and a thousand more every month, we wanted to show what a difference an individual can make." Hence this balloon stunt, which is not to be taken too literally. "Actually, collecting real exhaust would have been a fire hazard potentially more injurious than the bad air," says Schiff. "So we placed an air generator in the car's trunk and connected that to the back pipe. The shape needed to be slightly cartoony to better match the billowing exhaust cloud image in people's minds."