The purpose of this study is to determine whether Symbicort dosed according to the Symbicort Maintenance and Reliever Therapy (SMART) concept is superior to standard asthma treatment according to the local German treatment guidelines.

Inclusion Criteria:

• Patients with asthma, either well-controlled on a regular therapy with a combination of long-acting beta-agonists and inhaled corticosteroids or symptomatic on therapy with inhaled corticosteroids alone.

Exclusion Criteria:

• Any other significant lung disease other than asthma
• Any disease that might put patients at risk if they participate in the study