This document discusses the use of simulation in developing advanced driver assistance systems (ADAS) and autonomous vehicles. It emphasizes that simulation is critical to advance from the current state of ADAS to fully autonomous vehicles. Perception, prediction, and planning capabilities must be engineered into vehicles using sensors, artificial intelligence, and by addressing "edge cases" through techniques like Ansys SCADE Vision. Simulation allows generating large amounts of synthetic data to train AI systems for various driving scenarios more quickly than with real-world testing alone. Both physical testing and simulations involving hardware, software, and human factors are needed to achieve higher levels of autonomy beyond the initial ADAS functions.