Asthma is a chronic inflammatory disorder of the airways associated with bronchial hyperresponsiveness and permanent structural changes. Asthma can cause progressive lung impairment with a progressive decline of lung function leading to partially reversible or irreversible airway obstruction. These structural changes are called airway remodelling including loss of epithelial integrity, thickening of basement membrane, subepithelial fibrosis, goblet cell and submucosal gland enlargement, increase smooth muscle mass, decreased cartilage integrity and increased airway vascularity. These remodelling changes contribute to thickening of airway walls and consequently lead to airway narrowing, bronchial hyperresponsiveness, airway oedema and mucous hypersecretion. Airway remodelling is associated with a poorer clinical outcome among patients with asthma. Early diagnosis and prevention has the potential to decrease disease severity, to improve control and to prevent disease expression.