Fetal and neonatal alloimmune thrombocytopenia (AIT) is the commonest cause of severe thrombocytopenia in neonates, and of intracranial hemorrhage (ICH) in term neonates [1] (J Trop Pediatr, 1999; 45: 237). If a newborn is affected with AIT, the next child will likely be more severely affected, and therefore fetal thrombocytopenia will begin early in gestation [2, 3] (Arch Neurol, 1984; 41: 30; N Engl J Med 1997; 337: 22). This creates a risk of in utero ICH even if there was not one in the previous pregnancy. There are new developments in AIT in regard to diagnosis, treatment, and screening which will be the focus of this review.