In this case series, we report on five patients with influenza A (H1N1) who received extracorporeal membrane oxygenation (ECMO) treatment between July and December 2009 in the intensive care unit of Sir Charles Gairdner Hospital in Perth, Western Australia. In considering these cases, we highlight the indications, risks and potential benefits associated with ECMO, whose role remains, as yet, largely undefined in the setting of H1N1 critical illness.