Vehicle accidents caused by driver inattention and drowsiness represent a problem on both European and American roads. In-vehicle technical innovations, such as lane departure warning systems, are seen as a way to reduce the personal and material costs related to such accidents. Daimler-Benz and Odetics have developed and tested a lane departure warning system, based on image processing lane marking detection. A Time-to-Line-Crossing criterion was used to generate an acoustic warning in the form of a “rumble strip noise.” The latter was found to effect the fastest and most appropriate driver reaction. The technology developed for European roads and test results are discussed, as well as how these require adaptation for application to the US road system. A plea is made for enhancement of the technology and standardization of lane markings on American roads.