The recirculating ball steering is the state of the art steering system for heavy commercial vehicles. It is a variation on the older worm and sector design that transfers the steering wheel angle from the steering column to the wheels through the draglink and magnifies the input torque by means of an open centre hydraulic servo valve. This system design has been in use for decades and this probably will be the case for the far future too. However, the addition of mechatronics to this well-established lay out is on the verge of a break through. An electrical motor can either add torque or angle to the input shaft allowing for an alteration of the servo characteristics based on many other signals than just input torque and angle such as vehicle states, surrounding traffic, road and driver condition. Passenger cars have already introduced several kinds of angle or torque overlay systems and it is clear that its potential will be of interest for implementation to commercial vehicles. The project "Steering systems with active safety for heavy vehicles", is executed as a cooperation by Scania CV AB and KTH, aims at exploring the possibilities of these future technologies. As the title of the project states, large focus has been put on the safety improvements this could bring for road traffic. In most traffic incidents the driver has or could have had a decisive role in the outcome. Therefore, it is important to focus on the driver when searching for safety improvements. This can be done by putting the driver more in control of the situation by informing him better through feedback from the vehicle or by correctly interpreting his intentions resulting in a vehicle that does what the driver wants. Both aspects, feedback and response, are captured by the phrase "steering feel".