When choosing a drug regimen, physicians can rely on two models: their own clinical experience and results from clinical trials. Both options have problems. Overall, patients with persistent asthma symptoms often have improved outcomes with the use of long-term controller medications on a daily basis to prevent exacerbations of symptoms. Inhaled corticosteroids (ICSs) are generally recognized as being the most effective treatment for the underlying inflammatory characteristics of asthma. However, despite adequate dosing, some patients with persistent asthma remain symptomatic while taking an ICS. Therefore, it may be beneficial to administer combination therapy with an ICS and a long-acting β-agonist (LABA) in this subset of asthma patients. Another anti-inflammatory choice for persistent asthma is the leukotriene receptor antagonist (LTRA), either as monotherapy or in combination with an ICS. Regardless of what treatment regimen a physician chooses to prescribe, the choice of medication depends on many factors, including patient preference, physician comfort with the regimen, and cost.