A major problem in reconstructive and plastic surgery of the face is the assessment of exact distances between certain points of reference across facial contours. Incorrect estimation of these variables produces unsatisfactory postoperative anatomical results. Therefore a method, which permits exact measurements using stereoscopic photography of models, was tested. On the models quantitative studies of the effects of surgical techniques were made. Facial asymmetry and various phases of facial animation can be assessed and documented, and the progress of expanding tumours can likewise be followed.