OBJECTIVES: Crisis resource management principles dictate appropriate distribution of mental and/or physical workload so as not to overwhelm any one team member. Workload during pediatric emergencies is not well studied. The National Aeronautics and Space Administration-Task Load Index is a multidimensional tool designed to assess workload validated in multiple settings. Low workload is defined as less than 40, moderate 40-60, and greater than 60 signify high workloads. Our hypothesis is that workload among both team leaders and team members is moderate to high during a simulated pediatric sepsis scenario and that team leaders would have a higher workload than team members. DESIGN: Multicenter observational study. SETTING: Nine pediatric simulation centers (five United States, three Canada, and one United Kingdom). PATIENTS: Team leaders and team members during a 12-minute pediatric sepsis scenario. INTERVENTIONS: National Aeronautics and Space Administration-Task Load Index. MEASUREMENTS AND MAIN RESULTS: One hundred twenty-seven teams were recruited from nine sites. One hundred twenty-seven team leaders and 253 team members completed the National Aeronautics and Space Administration-Task Load Index. Team leader had significantly higher overall workload than team member (51 +/- 11 vs 44 +/- 13; p < 0.01). Team leader had higher workloads in all subcategories except in performance where the values were equal and in physical demand where team members were higher than team leaders (29 +/- 22 vs 18 +/- 16; p < 0.01). The highest category for each group was mental 73 +/- 13 for team leader and 60 +/- 20 for team member. For team leader, two categories, mental (73 +/- 17) and effort (66 +/- 16), were high workload, most domains for team member were moderate workload levels. CONCLUSIONS: Team leader and team member are under moderate workloads during a pediatric sepsis scenario with team leader under high workloads (> 60) in the mental demand and effort subscales. Team leader average significantly higher workloads. Consideration of decreasing team leader responsibilities may improve team workload distribution.