Purpose. Craniosynostosis is routinely diagnosed by CT scans, but recent publications, and the National Cancer Institute, have raised concerns about associated ionizing radiation (developmental delays and tumor induction). This study examines the diagnostic accuracy of the physical exam for single sutural synostoses. Methods. This prospective, multi-center, outcome assessment included all single sutural synostosis seen by craniofacial surgeons (1-18 years experience) at four centers over a one-year period. Clinical diagnoses were compared to CT scan evaluations, and the utility of scans during surgical repair was assessed. Results. Sixty-seven patients were clinically diagnosed with sutural craniosynostosis (mean = 7-months). Sixty-six of 67 patients were diagnosed with craniosynostosis by CT scan for a diagnostic accuracy exceeding 98%. One suspected lambdoid synostosis was radiologically diagnosed with positional plagiocephaly. Three out of four craniofacial surgeons scored CT scans as “unnecessary” for surgical correction. Conclusions: Craniofacial surgeons, with various experience levels, were able to accurately diagnose single sutural synostosis by physical examination alone. Considering potential side effects from ionizing radiation, sedation risks, and costs, surgeons may wish to reserve CT scans only for infants with suspected single sutural craniosynostosis in whom the physical examination is not clearly diagnostic.