A recent transportation conference demonstrated a possible advancement in automotive safety: cars that communicate with each other and warn drivers of impending collisions. Later this summer, the government will begin a year-long test involving nearly 3,000 vehicles. The vehicles will be equipped to continuously “talk” over wireless networks, exchanging information on location, direction, and speed with other similarly equipped cars within about 1,000 feet. After analyzing the data, a computer issues danger warnings to drivers, often before they can see the other vehicle. This vehicle-to-vehicle communication, or V2V, could even be used to take control of a car or prevent an accident by applying brakes when the driver reacts too slowly to a warning.