The Insurance Institute for Highway Safety (IIHS) is a U.S. nonprofit organization funded by auto insurance companies, established in 1959 and headquartered in Arlington, Virginia. It works to reduce the number of motor vehicle traffic collisions, and the rate of injuries and amount of property damage in the crashes that still occur. It carries out research and produces ratings for popular passenger vehicles as well as for certain consumer products such as child car booster seats. It also conducts research on road design and traffic regulations, and has been involved in promoting policy decisions. 
The Institute's front crash test differs from that of the U.S. government's National Highway Traffic Safety Administration (NHTSA) New Car Assessment Program (NCAP) in that its tests are offset. This test exposes 40% of the front of the vehicle to an impact with a deformable barrier at approximately 40 mph (65 km/h). The IIHS began this crash test in January 1995. 
The IIHS evaluates six individual categories, assigning each a "Good", "Acceptable", "Marginal", or "Poor" rating before determining the vehicle's overall frontal impact rating. 
As with the NHTSA's frontal impact test, vehicles across different weight categories may not be directly compared. This is because the heavier vehicle is generally considered to have an advantage if it encounters a lighter vehicle or is involved in a single-vehicle crash. The IIHS demonstrated this by crashing three midsize sedans with three smaller "Good" rated minicars. For example, three minicars were rated "Poor" in these special offset head-on car-to-car tests in 2009, while the midsize cars rated "Good" or "Acceptable". 
On August 14, 2012, IIHS released the first results for a second, more demanding frontal offset test. The new test, which is used in addition to the 40% offset test introduced in 1995, subjects only 25% of the front end of the vehicle to a 40 mph impact. The new test is far more demanding on the vehicle structure than the 40% offset test. In the first round of test, composed of 11 midsized luxury and near-luxury vehicles, most vehicles did poorly; only three vehicles received "good" or "acceptable" ratings. 
The rating system is similar to the 40% offset, but has some key differences: hip/thigh and lower leg/foot ratings replace individual ratings for each leg and foot, and full score cannot be attained without deployment of front and side curtain airbags (due to the severe side movement often resulting from this test). 
A Medical College of Wisconsin study found small-overlap collisions result in increased head, chest, spine, hip, and pelvis injuries. This sort of collision is common on two-lane roads with two-way traffic where a center median is absent. Single vehicle crashes (into a tree or a pole) account for 40 percent of small-overlap crashes.  According to the IIHS, 25% of frontal crash deaths are due to small overlap crashes, with the outer front wheel first to receive the impact forces rather than the more central crash absorbing structure. 
The IIHS has since tested family cars,  compact cars,   minicars,  small  and midsized   SUVs, minivans,  muscle cars  and large pickup trucks  through the small-overlap test.
In 2009, the IIHS celebrated its 50th anniversary. To illustrate how much automotive safety has progressed in five decades, IIHS tested a 1959 Chevrolet Bel Air crashing head-on, 40% offset with a 2009 Chevrolet Malibu at 40 mph.  It put the video of the crash on the Internet and "the results were no surprise to anyone with a passing familiarity with cars."  The Bel Air's occupant compartment was extensively damaged by the crash. Coupled with the car's lack of modern safety features such as airbags and seat belts, this resulted in the crash test dummy in the Bel Air recording forces that would have probably caused fatal injuries to a real driver. They "would not only hit the inside of the car and experience a large (and damaging acceleration) but the car would smash you on the inside."  Sophisticated engineering and high-strength steel give modern vehicles a huge advantage. 
This tests the vehicle's driver seat to determine effectiveness of the head restraints.  The driver's seat is placed on a sled to mimic rear-end collisions at 20 mph. Rear-end collisions at low to moderate speeds typically do not result in serious injuries but they are common.  In 2005 the IIHS estimated 25% of medical costs were related to whiplash injuries.
In the United States rollovers accounted for nearly 25% of passenger vehicle fatalities. Features such as electronic stability control are proven to significantly reduce rollovers and lane departure warning systems may also help. Rollover sensing side curtain airbags also help to minimize injuries in the event of a rollover. 
A maximum of 6 points are awarded. The points are awarded if the front crash prevention system meets government criteria, and whether it can reduce the speed or avoid the crash at both 12 and 25 mph (20-40 km/h). Vehicles that earn one point qualifies as a "basic" rating, while 2 to 4 points means the vehicle earns an "advanced" rating. A "superior" rating is given only if the vehicle earns 5 to 6 points on that test. 
In March 2016, the IIHS released ratings for headlight performance. Their first test involved family cars, and most earned marginal or poor ratings. Only one vehicle, the Toyota Prius V, earned a good rating when equipped with specific headlights.  The Institute evaluated headlights for small SUVs 4 months later, and none of the vehicles tested earn a good rating.  On October 2016, they released ratings for pickup trucks, and the Honda Ridgeline was the only pickup to earn a good rating on the headlights test. 
The Top Safety Pick is an annual award to the best-performing cars of the year. To receive a Top Safety Pick, the vehicle must receive "Good" overall marks in the moderate overlap front, driver-side small overlap front, side, roof strength and seat head restraint tests, regardless of their rating in the passenger-side small overlap front test. Vehicles must also be available with headlights rated acceptable or good and a front crash prevention system rated superior or advanced. The Top Safety Pick+ award is given to vehicles that meet all the criteria for a Top Safety Pick, but also are available with good rated headlights and receive a rating of acceptable or good in the passenger-side small overlap test. 
- BeSeatSmart Child Passenger Safety Program
- Head injury criterion
- National Highway Traffic Safety Administration
- New Car Assessment Program
- Euro NCAP
- "Regulatory documents". Iihs.org. Retrieved 2017-10-08.
- "Frontal crash tests". Iihs.org. Retrieved 2017-10-08.
- Weberillustrations, Bob. "Cars.com". Cars.com. Retrieved 2011-11-13.
- "IIHS.org". IIHS.org. 2009-04-14. Retrieved 2011-11-13.
- "IIHS raises the bar with new crash test". Iihs.org. 2012-08-14. Retrieved 2017-10-08.
- "IIHS.org". IIHS.org. 2012-08-14. Retrieved 2012-08-14.
- "New car crash test promises to make a big safety impact". News.consumerreports.org. 2012-08-14. Retrieved 2017-10-08.
- "Honda, Volvo models get high marks in new overlap crash tests". Autonews.com. 2013-03-07. Retrieved 2017-10-08.
- "Family cars trump luxury models in new crash test". Iihs.org. 2012-12-20. Retrieved 2017-10-08.
- "Small overlap front test challenges small cars". Iihs.org. 2013-08-08. Retrieved 2017-10-08.
- "Small car ratings vary in small overlap test". Iihs.org. 2014-07-30. Retrieved 2017-10-08.
- "Minicars fall short in tough frontal crash test". Iihs.org. 2014-02-20. Retrieved 2017-10-08.
- "Redesigned Subaru Forester aces tough new crash test". Iihs.org. 2013-05-16. Retrieved 2017-10-08.
- "Small overlap test stymies midsize SUVs". Iihs.org. 2014-04-08. Retrieved 2017-10-08.
- "Midsize SUVs' ratings are mixed". Iihs.org. 2015-05-12. Retrieved 2017-10-08.
- "Muscle cars fall short of safety awards". Iihs.org. 2016-05-24. Retrieved 2017-10-08.
- "Pickups struggle with small overlap test". Iihs.org. 2016-04-12. Retrieved 2017-10-08.
- Jensen, Christopher (September 17, 2009). "A 2009 Chevy Malibu Destroys a 1959 Bel Air -- Literally". The New York Times. Retrieved January 17, 2018.
- Northrup, Laura (September 23, 2009). "Crash Test Wars: 1959 Chevy Bel Air VS 2009 Chevy Malibu". Consumerist. Retrieved January 17, 2018.
- Allain, Rhett (December 18, 2010). "Crash Test: 2009 Malibu vs. 1959 Bel Air". Wired. Retrieved January 17, 2018.
- "IIHS.org". IIHS.org. Retrieved 2014-05-27.
- "IIHS.org". IIHS.org. Archived from the original on 2011-11-08. Retrieved 2011-11-13.
- "Blogs.consumerreports.org". Blogs.consumerreports.org. 2009-03-24. Archived from the original on 2010-05-30. Retrieved 2011-11-13.
- "Front crash prevention tests". Iihs.org. Retrieved 2017-10-08.
- "New IIHS ratings show most headlights are lacking". Iihs.org. 2016-03-30. Retrieved 2017-10-08.
- "Most small SUV headlights rate poor". Iihs.org. 2016-07-12. Retrieved 2017-10-08.
- "Pickups fall short in headlight testing". Iihs.org. 2016-10-25. Retrieved 2017-10-08.
- "IIHS safety ratings". IIHS. Retrieved 2018-01-29.