The goal of the SARTRE (Safe Road Trains for the Environment) project is to make progress in “intelligent” transport systems of the future, specifically in those that enable travelling in assisted convoy of between six and eight cars (road trains) and led by a truck as a guide vehicle. The project, apart from freeing motorists from driving, promises much greater safety and fuel savings estimated to be 20%, due to the reduction in air resistance. During the road train journeys and with wireless assistance, drivers will be able to read, rest, eat, make phone calls, and so on. The consortium drawing up this project is made up of seven partners, amongst them Volvo, IKA and IDIADA, and from sectors such as the car industry, public transport operators, universities and other technological centres. A total budget of 19 million euros has been earmarked for the project, for the 2009-2012 period. Field trials will be carried out in Spain next year, 2011. The Automobile Unit at Tecnalia is responsible, within the SARTRE project, for the analysis of human behaviour related to , the system whereby vehicles drive themselves. The factors and risks for humans with this technology will be analysed. As regards the implementation of the systems, SARTRE also forms part of the hardware and software architecture of HMIs (Human Machine Interfaces), which are to be installed in the vehicles and which will tell the driver when and how to react. For example, when the steering wheel of the vehicle is let go, the driving will pass to automatic, and vice versa.