One of the main actual challenges that the transport and planning sector has to face is the improvement of its energy and economic efficiency. In this issue, road transport has been improving its efficiency through different solutions, as new engines, better tires, less emissions and many other developments. The aim of this project was to introduce Longer and Heavier Vehicles (LHV), commonly known as MegaTrucks, as an alternative to road freight transport. A description of these new vehicles was given as well as the actual situation in Europe. The second part of this project focused on road safety regarding MegaTrucks. From an individual point of view, the individual safety of a LHV might be lower but, at the same time, benefits regarding collective road safety might appear. At the end, a simulation tool was used to predict the change in user behaviour when driving together with MegaTrucks. The results stated that the impact on collective road safety is neutral while there are some economic benefits for the private investors and government. This paper tries to summarize the main important effects from LHV towards the road network and its users.