In the descriptions of how variable takt works in Chap. 4, we have not yet answered a crucial question: How are the takt time groups and the associated takt times of the relevant assembly portfolio determined? According to our previous analyses, implementations, and experiences with variable takt, this is one of the most complex questions in this context. For this reason, we have dedicated a separate chapter to this issue. We start with a presentation of visualizations of takt time groups at Audi. We extend this with the help of our understanding of products and options from Sect. 2.4 and derive a first qualitative procedure for the determination of takt time groups. In Sect. 5.3, we introduce the workload equilibrium view, derive a model for defining takt time groups based on it, and create a heuristic algorithm—the VTGA. These elaborations are mainly based on the work of Moench et al. (2020). We summarize the findings of all sections of this chapter with the VTGTP (Variable Takt time Group Transformation Process), which we use to describe an approach to determine the essential parameters when converting an assembly from fixed to variable takt. Finally, we apply the VTGTP in a case study of the introduction of variable takt in the assembly of Canyon Bicycles and show the great potential of variable takt to increase productivity.