The invention relates to a method by which a mold for casting, such as metal casting, of dental prostheses is prepared, with the step of: preparing the mold on the basis of mold model data with a CAM/CAD method. Furthermore, the invention relates to a method for the determination of a shape of a mold for casting, such as metal casting, of dental prostheses with the step of: creating mold model data describing the shape of the mold.