Puerto Rico has high rates of pediatric asthma and morbidity associated in part with poor family asthma management and low rates of controller medication use. A previous study found a family management intervention called CALMA to be effective in reducing asthma symptoms and service utilization. However, CALMA was not effective in increasing the use of controller medications. CALMA- plus was developed to address this issue by adding to CALMA components of educational training of physicians and nurses, and screening for asthma in clinics serving Medicaid Puerto Rican children with persistent asthma. A total of 404 children in eight clinics were studied after forming four pairs of clinics and randomizing the clinics (1:1) to CALMA-only or CALMA-plus within each pair. After adjusting for clinic variation, the study failed to demonstrate that the CALMA-plus intervention was more efficacious than the CALMA- only intervention for increasing reported controller medication use or decreasing symptoms in children with persistent asthma. Both groups had lower rates of asthma symptoms and service utilization consistent with previous results of the CALMA-only intervention. Limitations of the study were small number of clinics available, comparison of the experimental intervention with an evidence based intervention, and limited exposure to some aspects of the intervention. More effective interventions may include aggressive case management, and providing the physician with more relevant information.