Introduction: Respiratory distress accounts for approximately 14% of all pediatric emergency medical services (EMS) encounters, with asthma being the most common diagnosis. In the emergency department (ED), early administration of systemic corticosteroids decreases hospital admission and speeds resolution of symptoms. For children treated by EMS, there is an opportunity for earlier corticosteroid administration. Most EMS agencies carry intravenous (IV) corticosteroids; yet given the challenges and low rates of EMS pediatric IV placement, oral corticosteroids (OCS) are a logical alternative. However, previous single-agency studies showed low adoption of OCS. Therefore, qualitative study of OCS implementation by EMS is warranted.Methods: This study's objective was to explore uptake and implementation of OCS for pediatric asthma treatment through semi-structured interviews and focus groups with EMS clinicians. We thematically coded and analyzed transcripts using the domains and constructs of the Consolidated Framework for Implementation Research (CFIR) to identify barriers and facilitators that most strongly influenced OCS implementation and adoption by EMS clinicians.Results: We conducted five focus groups with a total of ten EMS clinicians from four EMS systems: one urban region with multiple agencies that hosted two focus groups, one suburban agency, one rural agency, and a mixed rural/suburban agency. Of the 36 CFIR constructs, 31 were addressed in the interviews. Most constructs coded were in the CFIR domains of the inner setting and characteristics of individuals, indicating that EMS agency factors as well as EMS clinician characteristics were impactful for implementation. Barriers to OCS adoption included unfamiliarity and inexperience with pediatric patients and pediatric dosing, and lack of knowledge of the benefits of corticosteroids. Facilitators included friendly competition with colleagues, having a pediatric medical director, and feedback from receiving EDs on patient outcomes.Conclusion: This qualitative focus group study of OCS implementation by EMS clinicians for the treatment of pediatric asthma found many barriers and facilitators that mapped to the structure of EMS agencies and characteristics of individual EMS clinicians. To fully implement this evidence-based intervention for pediatric asthma, more education on the intervention is required, and EMS clinicians will benefit from further pediatric training.