The majority of paved roads in Germany are of asphalt construction. However, the steadily increasing volume of traffic is increasingly causing deformation of the surface of asphalt pavements, e.g. rutting or washboard-like bulges. Due to the thermoplastic behavior of asphalt and the associated limited resistance to deformation, these deformations recur at regular intervals even after renewal. Additional costs are incurred for repair and due to restrictions on use. Concrete pavements, on the other hand, are resistant to deformation on the surface over the long term. Rutting does not occur even under very high truck loads. The whitetopping method was developed in the USA as early as the 1920s and has since been regularly used to rehabilitate deteriorated asphalt roads. In this process, a new concrete surface course is placed on the deformed or - at the end of its service life - substantially fatigued existing road structure. The remaining load-bearing capacity of the existing structure is recorded and taken into account in the design of the layer thickness. As a result, "whitetopping" pavements are generally thinner than newly constructed concrete pavements. The main arguments in favor of this construction method were and still are that the deformed or deteriorated pavement can be left in place and thus the existing construction materials can continue to be used in their entirety. Compared with the fundamental renewal of a deteriorated structure, the construction time is also significantly shortened and the construction costs reduced. The research project funded by the German Federal Highway Research Institute aims to establish the technical basis for the successful application of the "whitetopping" construction method under the specific German construction, traffic and climatic conditions. The project is based on international experience and the theoretical, laboratory and practical findings of a research project on the development of ultra-thin concrete pavements, which is also being carried out at the University of Kassel.