Budesonide/formoterol is a combination of an inhaled corticosteroid plus a long-acting beta(2)-agonist available as a dry-powder inhaler for the indication of asthma and chronic obstructive pulmonary disease in various countries outside of the USA and as a pressurized metered-dose inhaler in the USA for the indication of asthma. Clinical studies have shown that budesonide/formoterol is significantly more effective than an equivalent or higher dose of budesonide or fluticasone propionate alone in patients with moderate-to-severe disease, and at least as effective as its two components administered via separate inhalers in asthmatics with predominantly moderate to severe persistent disease. Budesonide/formoterol is effective when administered both once or twice daily. Adjustable maintenance dosing with budesonide/formoterol has been shown to provide equivalent or better asthma control with a significantly lower amount of study drug use compared with fixed dosing. The rapid onset of action of budesonide/formoterol, predominantly due to formoterol, as well as its favorable dose-response, has prompted budesonide/formoterol to be used as both a maintenance and reliever medication, referred to as the Symbicort maintenance and reliever therapy (SMART) dosing regimen in several countries. Use of this approach has resulted in studies evaluating SMART, demonstrating significantly lower rates of exacerbations and reliever medication use compared with fixed-dosing regimens in asthma.