Adaptive Cruise Control (ACC) is currently one of the main control system focuses of vehicle and vehicle component manufacturers. Currently it is seen as a comfort system, reducing driver fatigue in heavy traffic, but it has the possibility to provide a lot of safety related features in the near future and becoming an integral part of an Intelligent Transport System (ITS). Incorporating ACC into an existing vehicle simulation system allows faster system development and removes safety issues from system testing as the vehicle model, complete with control systems, can be tested on the computer rather than on the street. An ACC system, which in this implementation also requires a vehicle dynamics controller (VDC or ESP(exp TM)), has been incorporated into the vehicle simulation package FASIM C++. This provides a powerful tool to develop ACC and extend its function, reducing development time and removing the risk to personal that occurs when such vehicle control systems are tested under driving conditions (normal or otherwise). The complete system is also a typical example of a mechatronic system. This paper discusses the advantages of simulating with ACC, suggests some extensions that would allow it to be turned into an Advanced Driver Assistance (ADA) system for incorporation into an ITS, and presents some preliminary simulation results.