Forty patients with premature craniosynostosis of variable extent and severity were subjected to cephalometry. The majority of the children and adolescents involved had undergone bilateral cranial fenestration at age 6 months to 11 years. Lateral cephalometric radiographs were used for analysis. The measurements obtained were compared with normal values of comparable age groups. In two thirds of the patients examined facial skull growth was found to be impaired, the clinical appearance ranging from pronounced faciostenosis to abortive forms. In some cases the clinical appearance was normal. One of the conclusions derived from the cephalometric data is that inhibited growth primarily affects the anterior portions of the skull base, which are found to be shorter than normal. The defect appears to involve the spheno-ethmoidal, intersphenoidal and sphenofrontal synochondroses.