‘Idiopathic neonatal hepatitis’ is a term that has traditionally been used to denote a clinical syndrome manifest by prolonged jaundice in the neonate. This description is now used much less frequently because recent studies unite well-defined clinical, biochemical and molecular features of intrahepatic cholestasis into specific syndromes. Advances in the understanding of the molecular basis of cholestatic syndromes now enable the classification of syndromes based on biology and offer an opportunity to develop new diagnostic approaches and treatment strategies that take into account the genetic make-up of the child with cholestasis.