The objective of this study was to evaluate parental preference for the treatment of asthmatic children with oral montelukast sodium or inhaled cromolyn sodium. Additionally, we wanted to compare the two drugs in terms of patient preference for treatment, patient and parent satisfaction with treatment, frequency of inhaled albuterol use, adherence to treatment, and safety. This was a 12-week randomized, open-label, crossover study conducted in 42 primary care and asthma/allergy specialty centers in the United States. Three hundred thirty-three asthmatic patients, ages 6 to 11 years, who had a forced expiratory volume in 1 second (FEV1) of 60%-85% (inclusive) of predicted value with > or = 12% reversibility after administration of an inhaled beta-agonist and who used albuterol on at least 7 of the last 14 days of the run-in period. After a 2- to 3-week run-in period, patients were randomized either to 4 weeks of montelukast (5-mg chewable tablet once daily) followed by a 2-week washout period, then 4 weeks of cromolyn (two puffs 4 times daily from a metered-dose inhaler) or to the reverse sequence. More parents preferred montelukast (87%) than cromolyn (12%; p < 0.001). More patients preferred montelukast (82%) than cromolyn (17%; p < 0.001). Daily albuterol use (puffs/day) was reduced by 38% during montelukast therapy vs. 23% during cromolyn therapy. Seventy-eight percent of patients reported being highly adherent to montelukast therapy compared with 42% to cromolyn therapy (p < 0.001). Fewer patients receiving montelukast discontinued because of asthma exacerbation (1.0% vs. 5.0%, respectively), and fewer patients reported worsening asthma while receiving montelukast (3.5% vs. 7.5%, p = 0.036). Parents' and patients' preference, parents' and patients' satisfaction, and patients' adherence to therapy were all significantly better with oral montelukast compared with inhaled cromolyn. Beta-agonist use was decreased when taking montelukast, which was safe and well-tolerated.