Hemifacial hyperplasia is a developmental disorder characterized by a marked unilateral asymmetry. The etiology is unknown, although several factors have been described. It involves not only the hard tissues of the face, but the soft tissues as well. A case report of an adult woman with hemifacial hyperplasia highlighting the clinical significance is presented. Schlagwörter: congenital anomaly, development disorder, hemifacial asymmetry, hemifacial hyperplasia, hemifacial hypertrophy, osteotomies