This paper addresses the modeling of traffic flows with intelligent cars and intelligent roads. It will describe the modeling approach MIXIC and review the results for different ADA systems: Adaptive Cruise Control, a special lane for Intelligent Vehicles, cooperative following and external speed assistance. In general there are clear indications for an improvement in traffic safety. It also shows that traffic efficiency impacts are limited and in specific conditions even negative. Given the increasing attention 10 more advanced driver assistance system, the paper proposes new research directions Assistance' and advanced modeling techniques toward 'integrated driver assistance'.