To determine the sensitivity of parental suspicion of concussion relative to paediatric emergency physicians in children who presented to an emergency department (ED) with a head injury. A secondary objective was to examine the variables associated with parental suspicion of concussion concordant with that of a physician. Parents of children five to 18 years of age presenting to an urban paediatric ED with a nonstructural head injury completed a 24-item questionnaire. Of the 577 eligible parents, 495 (85.8%) consented to participate. The sensitivity of parental suspicion for concussion was 40.0% (95% CI 33.2% to 47.2%), while the specificity was 58.3% (95% CI 52.4% to 64.0%). The variable of child age ≥10 years was associated with an increased odds (OR 3.0) of a parental suspicion of concussion concordant with that of a physician; parent age, parent sex, mechanism of head injury and history of concussion in the child were not. Although 453 (91.5%) parents would stop activity if they believed their child sustained a concussion, only 159 (32.1%) were familiar with return-to-play guidelines. Parents often did not suspect a concussion when it was ultimately diagnosed by a paediatric emergency physician, although they were more likely to do so in older children. Only approximately one-third were aware of return-to-play guidelines. To enhance the potential for parent-driven advocacy in the recognition and management of concussion, these data support the need for increased parental education on this injury.