With EU funding of the ISI-PADAS project, European scientists developed an integrated driver-vehicle-environment simulation approach to support risk-based design (RBD) and approval of new PADAS. A key component of the ISI-PADAS system is advanced driver modelling incorporating key aspects of human behaviour, cognition and decision making. Through extensive empirical studies with human drivers in real and simulated situations together with modern algorithms, scientists developed tools to predict correct and erroneous driver behaviour. They also enhanced assessment of the risk of human error and used it in RBD of advanced control systems for PADAS. Investigators then integrated the driver models with vehicle and environment models to produce the ISI-PADAS Joint Driver-Vehicle-Environment (JDVE) simulation platform. The JDVE supports the risk analyst by providing expanded human performance event trees (EHPET) for various scenarios. The ISI-PADAS JDVE simulation platform will facilitate RBD of better PADAS through extensive integration with advanced driver models. The methodology is expected to significantly reduce human error as well as injuries and mortality associated with traffic accidents.