Automatic Cruise Control(ACC) will provide a safe way of driving and will probably reduce the chances of accidents by controlling the speed. A good ACC system accelerates aggressively to the desired speed without overshooting, and maintains the speed with little deviation, no matter how much weight is in the car or how steep the path. Different traffic densities found to demand different kind of behaviors from vehicles to optimize the usage of roadways. In fact, studies have shown that the use of ACC in congested traffic often results in excessive braking and accelerations. This work proposes a methodology in which ACC is used at high speed situations where the traffic density is low to moderate, and it has stop and go capabilities at critical situations. The objective of the control structure is to adapt the vehicle's speed to the traffic environment. A sensor system attached in the front of the vehicle is used to detect whether slower moving vehicles are in the ACC vehicle's path. If a slower moving vehicle is detected, the ACC system will slow down the vehicle and control the clearance gap between the host and the forward vehicle. If the forward vehicle is no longer in the ACC vehicle's path, the ACC system will accelerate the vehicle to its set cruise control speed. This control structure also ensures that brake is issued before critical distance is reached or the occurrence of possible collision.