Purpose of review: In spite of the availability of antiviral therapy for the treatment of neonatal herpes simplex virus infections, the outcome remains poor, particularly for babies with disseminated multi-organ infection or central nervous system disease. This review considers recent advances that impact on disease management. Recent findings: Two areas of investigation have impacted on our understanding of neonatal herpes simplex virus infection. First, the transmission of infection from mother to baby has been clarified by extensive epidemiological investigations of genital herpes in pregnant women at term. Risk factors for neonatal herpes simplex virus disease include first-episode maternal infection in the third trimester, invasive monitoring, delivery before 38 weeks, and maternal age of less than 21 years. Regarding the management of neonatal herpes simplex virus disease, the utilization of high-dose acyclovir (20 mg/kg every 8 h) for 21 days significantly reduces mortality for babies with either encephalitis or disseminated disease. Summary: Recent findings from epidemiological studies have identified women at risk of delivering a child who develops neonatal herpes simplex virus infection, and suggest methods to decrease maternal-fetal transmission. If infection is identified in the pregnant woman, cesarean delivery decreases the frequency of neonatal disease. With neonatal disease, acyclovir should be administered promptly at higher dosages and for longer periods than previously reported. © 2004 Lippincott Williams & Wilkins.