On the basis of the well recognised role of inflammation in the pathogenesis of asthma, anti-inflammatory therapy, in the form of inhaled corticosteroids, has become the mainstay of treatment in patients with persistent asthma. Budesonide inhalation suspension (BIS) is a nonhalogenated corticosteroid with a high ratio of local anti-inflammatory activity to systemic activity. Furthermore, BIS is approved in >70 countries for the maintenance treatment of bronchial asthma in both paediatric and adult patients (approval is limited to paediatric patients in the US and France).Randomised, double-blind, placebo-controlled trials conducted in >1000 children have demonstrated the efficacy of BIS in children with persistent asthma of varying degrees of severity. In children frequently hospitalised with uncontrolled asthma, initiation of BIS therapy can reduce the need for emergency intervention. Moreover, limited data suggest that BIS is effective for the treatment of acute exacerbations of asthma in children and may reduce the need for short courses of oral corticosteroids.BIS is well tolerated in children, with an adverse event profile similar to that of placebo, and no clinically relevant changes in adrenal function have been demonstrated during the course of short- and long-term (1-year) studies. Small but statistically significant reductions in growth velocity have been demonstrated with BIS over 1 year of treatment. However, available evidence suggests that growth effects are transient in children receiving budesonide and that these children eventually achieve full adult height.