Congenital and acquired infections of the central nervous system (CNS) pose a significant threat to the developing brain, even in the face of appropriate medical treatment. During the past five years, a number of reports have described the ultrasound features of intracranial infection, including echogenic sulci, extra-axial fluid collections, ventricular enlargement, calcifications, abnormal parenchymal echogenicity, abscess formation, cystic degeneration of the brain parenchyma, intraventricular echogenicity, ventricular septations and irregularity and prominence of the ventricular walls. These features permit ultrasound diagnosis of intracranial infection and help to guide decisions affecting patient management.