Inhaled therapy has a central place in the management of obstructive lung diseases, but a large number of patients are unable to use their inhalers correctly with a consequent reduction in therapeutic benefit. Correct use of inhalers is, therefore, crucial for efficient therapy, and acceptance of the device can improve patients' compliance. The choice of the most appropriate inhaler for a given patient is often not straightforward. The ease-of-use and performance characteristics of the inhaler will markedly influence patients' acceptance of the device, as well the patients' attitudes to their illness and chronic medication use in general. Choosing the most appropriate inhaler for a specific patient and regular assessment of ability to correctly use their inhaler will promote better adherence to therapy with improved disease outcome. Further, patients' preference for a particular inhaler should be taken into consideration. In patients with obstructive airway diseases, inhaler choice is as critical as the choice of medication itself.