Aim To present the methods and outcomes of stakeholder engagement in the development of interventions for children presenting to the emergency department (ED) for uncontrolled asthma. Methods We engaged stakeholders (caregivers, physicians, nurses, administrators) from six EDs in a three-phase process to: 1) Define design requirements; 2) Prototype and Refine; and 3) Evaluate. Results Interviews among 28 stakeholders yielded themes regarding in-home asthma management practices and ED discharge experiences. Quantitative and qualitative evaluation showed strong preference for the new discharge tool (CHICAGO Action Plan after ED discharge, CAPE) over current tools. Conclusions Engaging end-users in contextual inquiry resulted in CAPE, a new stakeholder-balanced discharge tool, which is being tested in a multi-center comparative effectiveness trial.