This paper provides an overview of the social-psychological factors that are likely to influence the trust and acceptance of shared SAE Level 4 Automated Vehicles (AVs). It begins with a short summary of what influences users’ engagement in ride-sharing for conventional vehicles, followed by the factors that affect user acceptance and trust of robotic systems. Using studies of human robot interaction (HRI), recommendations are made on how to improve users’ trust, acceptance and use of shared AVs. Results from real-world studies and on-line surveys provide some contradictory views regarding willingness to accept and use the systems, which may be partly due to the fact that on-line users have not had actual interactions with AVs. We recommend that the pathway to adoption and acceptance of AVs should be incremental and iterative, providing users with hands-on experience of the systems at every stage. This removes unrealistic, idealised, expectations, which can ultimately hamper acceptance. Manufacturers may also use new technologies, social-networks and crowd-sourcing techniques to receive feedback and input from consumers themselves, in order to increase adoption and acceptance of shared AVs.