The main objective of the ISi-PADAS project is to provide an innovative methodology to support risk based design and approval of Partially Autonomous Driver Assistance Systems (PADAS) focusing on elimination and mitigation of driver errors by an integrated Driver-Vehicle-Environment modelling approach. The methodology contributes to (1) halving the number of road fatalities by 2010 (respect to 2001 levels) and reducing number and severity of injuries caused by road accidents and to (2) decreasing the level of human error. These targets will be achieved through research and technology development in: (1) improved risk based design: implementation of a human error risk based approach for designing advanced control systems, such as PADAS; (2) advanced driver modelling: development of models for predicting correct and erroneous driver behaviour, based on modern approaches and algorithms, capable of capturing the key aspects of human behaviour, and retaining the fundamental characteristics of cognition and decision making; (3) Joined Driver-Vehicle-Environment Simulation Platform: integration of the driver models into a Driver-Vehicle-Environment computerised, fast running, and simple simulation tool for predicting driver behaviour and driver errors to be integrated in a risk based approach; (4) new knowledge about driver behaviour including errors: extensive empirical studies and experiments with human drivers in real cars and car simulators will lead to new insights in sources of accidents and potential counter measures as a basis for the driver model development. A target system will be developed to demonstrate the advantage of the new risk based design methodology with regard to an improved system design, a highly effective human error risk assessment and, consequently, an increased traffic safety.