Back pain is observed in a high percentage of professional drivers of heavy-duty vehicles and trucks. It was found that whole-body vibrations, prolonged sitting and posture, because of task handling and seating system, are the main factors in the development of back pain. The attenuation of vibrations and the provision of a good ergonomic posture at all times are therefore becoming more important. To achieve this a better knowledge of human behaviour towards vibrations and when seated on suspended seats is required using more appropriate evaluation techniques. The EC project SAFEGUARD aims at developing a new seat evaluation methodology where with controlled vibration tests and virtual reality simulations as many features as possible of human behaviour when seated on suspended seats are combined. The results of this combined methodology will lead to better understanding of the driver-seat-cabin system and the relation to comfort and health. They will also provide a more accurate way to interpret the efficiency of new seat features in improving comfort and health.