Inhaled corticosteroids are the foundation of asthma therapy and now, 50 years on from their introduction, is an appropriate time to summarise some of the key studies that have progressed the field. We can now make better decisions in selecting the optimal inhaled corticosteroid-based regimens and identifying likely responders, based on biomarkers and patient characteristics. Inhaled corticosteroids reduce the risk of asthma attacks, but do not alter the course of the disease. Asthma remission, which is as yet an undefined therapeutic goal, is the aim, but the role of inhaled corticosteroids is unclear.