Mild intermittent asthma (step 1) is treated with inhaled short-acting beta‑2 agonists (SABAs), as required. The introduction of regular preventer therapy with ICSs (step 2) should be considered when a person has had exacerbations of asthma in the previous 2 years, is using inhaled SABAs 3 times a week or more, is symptomatic 3 times a week or more, or is waking at night once a week because of asthma. Add-on therapy (step 3) involves the introduction of an additional therapy, the first choice of which is an inhaled LABA. Alternatives include orally administered leukotriene receptor antagonists, theophyllines and slow-release beta-2 agonist tablets, or increasing the dose of ICS. At step 4, further interventions may be considered if control remains inadequate on a dose of ICS that is equivalent to 800 micrograms per day of beclometasone dipropionate in combination with a LABA, or following an unsuccessful trial of a LABA. Options include increasing the dose of the ICS to 2000 micrograms beclometasone dipropionate equivalent per day or adding a leukotriene antagonist, a theophylline or a slow-release beta‑2 agonist tablet. At step 5, continuous or frequent courses of oral corticosteroids are introduced. The majority of people with asthma are treated at steps 1, 2 or 3.