With overall dimensions slightly increased, the new STS conveys more of the design flair that has become a Cadillac signature. Up front, the dual-textured, multi-faceted grille first seen on the Sixteen concept and incorporated on both the Escalade and soon-to-be-launched 2008 CTS, has been adapted to the STS, giving the luxury performance sedan a more sophisticated appearance. Vertically stacked headlamps with large, dual 70mm projector lenses are encased in an aluminized, single-piece bezel. High Intensity Discharge (HID) headlamps are now available on V-6 models.

Also available on V-6 models for the first time are Intellibeam headlamps. The headlamps automatically switch gradually from high beam to low beam when vehicles approach or the vehicle is approaching taillamps. The lower front fascia is a new design, with a new intake and grille patterned after current Cadillac 'V' cues. New, narrower side marker lamps are added.

Similarly, side air extractors, again inspired by the Sixteen and Escalade, are now incorporated in the front fenders of the STS.

New styling touches also include chrome-plated door handles and new lower rocker moldings that blend into the lower line of the vehicle for more presence and refinement.

At the rear, the new fascia is now body-color, and is highlighted with the addition of polished, aluminum three-inch exhaust tips.

New, polished 18-inch by 8-inch aluminum 14-spoke wheels are available. For these available wheels, Michelin W-rated, 235/50R18 tires are used up front, and the rear wheels are fitted with 255/45R18 all-season radials.

Inside, STS's luxurious interior includes a new steering wheel with available genuine Sapele Pommele wood trim. Sapele is an exotic wood more commonly used in fine furniture and musical instruments. A heated steering wheel also is available. The center stack of the instrument panel is revised with the addition of wood trim that has new metallic surroundings.

New, available features for the STS include a head-up display on V-6 models. The head-up display projects key driving information (such as speedometer ratings) onto the windshield, enabling drivers to keep their eyes on the road.