For the increasingly important preservation of existing structures, strengthening with carbon reinforced concrete has proven to be an effective option in recent years. With the CARBOrefit® process, this type of flexural strengthening has been approved by the building authorities in Germany. Thin layers of carbon reinforced concrete are applied to existing concrete structures for repair or to increase the load-bearing capacity. The materials, the dimensioning and the procedure, including the boundary conditions, are described in the general technical approval with the number Z-31.10-182 (DIBt, 2021) and are presented in this article. In addition, the requirements for contractors are specified.