Background and objectives Research suggests that parents of children supported on Extracorporeal Membrane Oxygenation (ECMO) may be at risk of posttraumatic stress symptoms (PTSS), although no specific investigations have been carried out. The current study explored PTSS in this group. Associations with family functioning and parenting self-esteem were also investigated. Method Parents were identified from the hospital database and recruited in a cross-sectional, single group design by postal invite. Participants (n = 52) completed questionnaires measuring PTSS, family functioning, parenting self- esteem, depression and anxiety. Results Participants reported levels of intrusion and hyperarousal symptoms which were not statistically different to those found in parents from a comparison paediatric population. Avoidance symptoms were significantly higher in the current sample. Participants reported significantly more effective family functioning than parents from a comparison paediatric population. Family functioning and parenting self-esteem were also greater than that reported in community samples. Family functioning was not independently 3 I DClinPsy project: PARENT EXPERIENCE OF ECMO associated with PTSS and PTSS were not independently associated with parenting self-esteem. Conclusions PTSS appear to be a problem for some parents of children supported on ECMO. While associations exist between family functioning, PTSS and parenting self-esteem, it seems likely that these are indirect relationships. 4