Intracranial pressure (ICP) and skull volume are intricately related. Craniosynostosis alters skull volume, and the many forms of craniosynostosis complicate the relationship to ICP even further. Patients with single-suture synostosis are less likely to experience elevated ICP than patients in whom multiple sutures, craniofacial syndromes, or both are involved. Among patients with more than one suture involved, the multifactorial mechanisms underlying elevated ICP include cephalocranial disproportion and venous outflow obstruction. Direct monitoring of ICP for at least 24 hours can aid in the diagnosis and decision making process. The management of craniosynostotic patients is diverse and necessitates a long-term plan for follow-up.