The City Automated Transport System (CATS) was a collaborative FP7 European project that lasted from 2010 to 2014. Its objective was to evaluate the feasibility and acceptability of driverless electric vehicles in European cities. This contribution explains how the project was implemented by 11 teams in five countries, culminating with practical trials of driverless vehicles in Strasbourg, France; Ploiesti, Romania; and Lausanne, Switzerland. The Navya vehicles used were able to transport up to eight passengers, in an open vehicle where passengers could recline against lumbar support cushions. After extensive road testing in Strasbourg, the final demonstration took place at the EPFL campus in Lausanne, where around 1600 people were transported safely during 16 days of vehicle operation. Three vehicles were used, a fourth remaining on campus as a back-up. Although no driver was present, a student was available on board of each vehicle to respond to questions from the passengers and to handle the three points on the 1.8 km route where there was insufficient leeway for two vehicles to pass each other. Passenger reactions to the driverless vehicle concept were collected by questionnaire and were overwhelmingly positive. Caveats include limited access for people with disabilities and the risk that a regular service based on this new concept might compete with walking and cycling rather than with transport by car. Implications for the acceptability of driverless electric vehicles in Europe and elsewhere are discussed.