Airway hyperresponsiveness, airway smooth muscle (ASM) hyperplasia and hypertrophy, airway inflammation and alterations in the extracellular matrix, in particular the thickness of the lamina reticularis, are all characteristics of chronic persistent asthma. How each of these characteristics interact to result in the pathology of asthma is slowly being elucidated through research addressing each of these points in laboratories all over the world. The smooth muscle cell is emerging as a key player with the capacity to influence all of these features. Precisely what role the ASM cell plays in asthma was the focus of a European Respiratory Society Scientific Symposium held at Gullmarsstrand, Sweden in June 2004.