Regulators and auto makers began paying attention to S.U.V. collisions with cars in response to a 1997 series in The New York Times. Before then, regulators had done more than 2000 tests without ever crashing an S.U.V. into a car, while automakers said that they did not look at compatibility in crashes when designing vehicles.

Sales of S.U.V.'s and pickups were booming, but automakers soon faced pressure from the National Highway Traffic Safety Administration, which threatened to impose mandatory regulations if the industry did not act.

In a landmark agreement in 2003, 15 automakers from four nations agreed that by late 2009, all S.U.V.'s and pickups would either be lower to the ground or built with an energy-absorbing beam that fits under the front and rear bumpers.

Of course, the success is only partial. Tens of millions of older models are still on the road. NHTSA's failure to act sooner means car passengers will continue to face increased risk until these older models are phased out over time.

Posted by Genevieve Smith, 11:34:16 AM