In this book, we explain a novel control approach based on fuzzy logic theory to help a driver maintain the kinetic balance of the vehicle. This controller can be integrated in the vehicle to use sensors and actuators in order to coordinate suspension, brakes and steering system in critical situations. The proposed approach investigates the vehicle dynamics instability based on fuzzy analysis of vehicle CG (center of gravity) behavior. An advantage of this controller is that it doesn't interfere with the driver's habit in vehicle control and it resumes functioning only in critical moments. Using various actuators and sensors, we introduce a new approach to detect vehicle dynamics instability and the turnover threshold. In addition, after describing the present fatigue detection systems, a fuzzy logic based approach has been proposed for real-time driver fatigue detection. Fuzzy logic based analysis of the parameters effective on vehicle driver's fatigue/drowsiness is the main objective of this book. Fuzzy analyzers of the proposed system use various sensors to detect fatigue crisis and prevent driver's fatigue in critical situations by alerting.