Ford is developing a technology that will enable cars to drive themselves when they encounter traffic jams, allowing the driver to relax and cutting congestion. Ford calls the system Traffic Jam Assist and says it will be ready by 2017 at the earliest. The system builds on Ford's Active Park Assist, which allows for automatic parking, and adaptive cruise control technologies. Ford says delays were reduced by one-fifth when one-quarter of the cars in a Ford-sponsored simulated study had Traffic Jam Assist activated.