The management of mild to severe croup has undergone dramatic changes in the last 5 years, primarily due to the increased understanding of the benefits of treating it with steroids. Steroids have been used in the treatment of croup for many years, but, until recently, their use has remained controversial. Earlier studies were often not blinded or used inappropriate outcome measures, such as respiratory rate, which have not proven appropriate. Two attempts to review the literature in 1980 and 1989 cautiously supported the use of steroids. Despite these recommendations many practitioners continued to view croup in most cases as a benign self-limited condition, and since steroids have potential side-effects, their use was not considered justified. More recently, however, a number of developments such as the successful use of the inhaled steroid budesonide and oral dexamethasone have reinforced the argument for using steroids. Recent work has also shown that both inhaled and systemic steroids work by 1 hour and dramatically reduce morbidity and hospitalization time. The demonstration that an oral dose of 0.15 mg/kg dexamethasone is as effective as larger doses has made the use of systemic steroids more acceptable to many practitioners. All children with croup severe enough to be admitted to hospital should receive steroids. Two recent studies have shown that steroids also benefitted children who presented to emergency departments for treatment, but whose croup was not considered severe enough for admission. The type of steroid, the dose, and the mode of administration will need to be decided by the attending clinician.