New generation of rotary transfer machines processing different models of parts is considered. In order to enhance the costeffectiveness of mixed-model rotary transfer machines, the problems of process planning for the parts to be machined and the configuration of a rotary transfer machine are integrated in the same optimisation problem. This problem is modelled as a combinatorial optimisation problem. The decisions to be taken simultaneously concern the orientation of parts for machining, the machining parameters for processing the parts as well as the configuration of machining units to be used at working positions of the machine. Constraints related to the design of such units – spindle heads, turrets – and working positions, as well as precedence constraints related to machining operations, are taken into account. The problem consists in minimising an estimated cost of the rotary transfer machine, while reaching a given output and satisfying all the constraints. The proposed methods to solve the problem are based on its MIP formulation. The optimisation techniques are validated on an industrial case study. Numerical experiments evaluate the efficiency of the approach against the variety of parts to be produced.