A double-blind cross-over trial lasting 4 weeks of beclomethasone dipopionate aerosol in thirty-nine children and young people with asthma already on oral corticosteroid treatment showed a significant beneficial effect which in most cases was maintained on continued open treatment for a further 4 weeks. An overall assessment based on several clinical observations and measurements suggested that twenty-four (62%) were improved while having beclomethasone dipropionate. After a month on known beclomethasone dipropionate fifteen patients had stopped oral corticosteroid treatment and five had reduced the dose without relapse. Response to treatment was not related to total IgE levels. No serious side effects were noted.