Disodium cromoglycate was introduced in the late 1960s as maintenance therapy for persistent asthma and as a modifier of exercise induced bronchoconstriction. It was the first treatment designed to manage the chronic nature of the disease and modify the inflammatory component without untoward systemic side effects. After its anti-inflammatory effects had been established,¹ clinical trial data began to appear in the late 1960s and, although it remains as an option in the 1995 British guidelines on asthma management,² its use was already in steep decline^3-4 and it has now become a minority therapeutic option. In the current issue of Thorax a systematic review is presented which argues against its continuation as an option for the management of persistent symptoms in childhood.⁵ Why has it taken so long for the evidence of few, if any, beneficial effects in the management of persistent childhood asthma to appear in the face of its virtual . . . [Full text of this article]