As part of the Cross-Ministerial Strategic Innovation Promotion Program of Automated Driving for Universal Services (SIP-adus) spearheaded by Japan’s Cabinet Office, we construct microeconomics-based models to simulate the market diffusion of AVs, using the predictions of these models as a common source of basic numerical data to characterize the impact of AVs in various sectors. In this chapter, we briefly introduce our way of classifying automated driving systems, and two models developed to simulate the diffusion of AVs. We then present the results of a variety of variable-sensitivity analyses conducted using these models, and their policy implications. The main finding of the analyses is that enhancement of consumer expectations will be crucial for ensuring the diffusion of AVs in the future.