When a rigid fixation of the mandibular sagittal split osteotomy is performed, the exact position of the condyle has to be maintained. We report a simple method for determining the preoperative position of the proximal segment. The method is fast and does not require additional technical equipment. Preliminary results indicate that a decrease in postoperative temporomandibular joint problems can be achieved by using this method. A follow-up will show whether the method also can decrease the incidence of skeletal relapse.