PURPOSE OF REVIEW: Atypical skull shapes occur in as many as 20% of infants. The purpose of this review is to discuss the clinical approach to the evaluation of a child with an abnormal head shape. Readers will learn how to identify the head shapes caused by environmental deformation and craniosynostosis. We also review recent findings with regard to the genetics of single-suture craniosynostosis. RECENT FINDINGS: Healthcare providers can use key aspects of the examination of a child with a head shape abnormality to differentiate positional deformity from craniosynostosis. Overlap between the genetic causes of isolated single-suture craniosynostosis and syndromic forms is discussed. SUMMARY: Pediatricians can identify the causes of the majority of head shape abnormalities by combining their understanding of normal calvarial growth with a careful physical examination. Molecular genetics is playing an increasing role in the evaluation of children with single-suture fusion.