In Insurance Institute for Highway Safety (IIHS) tests, the IS sedans earned top 'good' ratings for frontal and side impact, and just 'acceptable' in the seat-based rear impact test. And while the IS hasn't been rated in the heavily revised, more stringent tests being introduced by the federal government for the 2011 model year, It earned four stars in frontal protection and a mix of four and five stars for side protection in the former tests.
Standard stability control, side and side-curtain airbags, knee airbags, and anti-lock brakes are included in all IS sedans.
With the optional Pre-Collision System, the IS can anticipate when a crash is imminent; and if the onboard computer determines it's unavoidable, the system stiffens the suspension, tightens the seatbelts, and pre-initializes the brake assist in preparation for impact. It's packaged with the Dynamic Radar Cruise Control feature, which uses radar to detect obstacles out in front.