Distraction of the facial skeleton in case of severe deformities or malformations needs detailed and exact planning. In craniomaxillofacial surgery advances in imaging techniques and associated technologies have led to improved preoperative planning. Stereolithography models however do not fulfill the requirements for complex cranio-maxillofacial plastic and reconstructive procedures i.e. preoperative planning with virtual correction, intraoperative navigation and postoperative control. On the base of an axial spiral CT data set in our clinic an optical navigation system is used for preoperative planning and intraoperative controlling of tumor resection, adjuvant chemo- or radiotherapytherapy and complex cranio and maxillofacial reconstruction. We present the use of this technique for midface and mandible distraction. Preoperative planning including positioning of the distraction devices, navigational guided osteotomies and postoperative control will be demonstrated. Keywords: computer assisted surgery, distraction osteogenesis, maxillofacial surgery