<p>Positional skull flattening (or deformational plagiocephaly) presents as uni- or bilateral flattening of the occipital region. The incidence varies from 16–46.6% in the first months of life and is mainly caused by intrauterine positioning, instrumental delivery and in part because of preferred side/supine sleep positioning to prevent sudden infant death syndrome. These deformities can be diagnosed and classified on the basis of their clinical features (e.g. asymmetry of the ear anteriorly positioned on the affected side), supplemented in unclear cases by ultrasound of the cranial sutures. Differential diagnoses include craniosynostosis, torticollis and other causes of facial asymmetry. The main preventive and therapeutic measure is parent education to foster correct positioning habits (turning of the infant to the less favoured side; prone positioning on occasion when awake) and beneficial stimulation of the infant (to promote lying on the less favoured side). If the range of motion of the head is limited, physiotherapy may be effective as well as skull orthosis (splint) in severe cases. Parental concern about the deformity must not lead to less adherence to the important recommendation of a&#xa0;supine sleeping position.</p>