Introduction: The diagnosis of concussion is a critical step in the appropriate management of patients following minor head trauma. The authors hypothesized that wide practice variation exists among pediatric emergency medicine physicians in the application of physical and cognitive rest recommendations following an acute concussion. Methods: The authors developed a 35-item questionnaire incorporating case vignettes to examine pediatric emergency physician knowledge of concussion diagnosis, understanding of initial management using return-to-play/school/work guidelines, use of existing concussion protocols, and perceived barriers to protocol use. Using a modified Dillman technique, the authors distributed an online survey to members of Pediatric Emergency Research Canada, a national association of pediatric emergency physicians. Results: Of 176 potential participants, 115 (65%) responded to the questionnaire, 89% (95% confidence interval [CI]: 0.81, 0.93) of whom reported having diagnosed 20 or more concussions annually. Although 90% (95% CI: 0.83, 0.94) of respondents adequately diagnosed concussion, only 64% (95% CI: 0.54, 0.72) correctly applied graduated return-to-play guidelines. Cognitive rest recommendations were also frequently limited: 40% (95% CI: 0.31, 0.49) did not recommend school absence, 30% (95% CI: 0.22, 0.39) did not recommend schoolwork reduction, and 35% (95% CI: 0.27, 0.45) did not recommend limiting screen time. Eighty percent (95% CI: 0.72, 0.87) of respondents reported having used guidelines frequently or always to guide clinical decisions regarding concussion. Conclusion: Despite a proficiency in the diagnosis of concussion, pediatric emergency physicians exhibit wide variation in recommending the graduated return to play and cognitive rest following concussion.