This paper presents an extended workflow to improve the dynamic behaviour of machine tools that is fully controlled in the virtual reality environment (VR). The workflow utilizes a common platform for the visualization of results of an experimental modal analysis and the following structural dynamic modification to eliminate the weak points of the design. Based on the overlaid visualization of measured mode shapes, the calculated behaviour and the CAD-model of the machine combined with the parameter modifications in the same virtual reality environment, the VR based approach becomes a development tool that helps to immediately understand cause and effect of complex changes. The advantages of the presented approach are shown by investigating parameter modifications of an I-beam demonstrator and a machine tool.