5-axis milling is a technology used in many industries such as aerospace, automotive and die/mold for machining of complex surfaces. Cutting forces, form errors and chatter vibrations are among the most important limitations in these operations. Process models can be used for predictions and optimization in 5-axis milling. In this paper, the process models and their applications are presented. These methods are implemented in simulation software, and applied in machining of industrial parts where productivity increase for example cases is demonstrated.