Cyclosporin A is a potent immunosuppressive agent which inhibits activation of T cells and other inflammatory cells. It has been shown to be of clinical benefit in patients with corticosteroid-dependent asthma, but there are no data on its in vivo effects on airways inflammation. In this report, we describe the case of a 47-year-old man with chronic severe corticosteroid-dependent asthma who made a dramatic clinical response to therapy with cyclosporin A. Fibreoptic bronchoscopy with bronchoalveolar lavage and endobronchial biopsy were performed before and after a 12-month period of treatment with cyclosporin A and demonstrated a concomitant reduction in airway inflammatory indices.