It is estimated that in excess of 10,000 critically ill or injured patients are transferred between hospitals each year in the UK. The optimal mode of transport selected for a patient transfer depends upon a number of factors. These include: the indication for, and urgency of, transfer; time to organize/mobilize transport; weather and traffic conditions; space; and cost. Current guidelines recommend that a minimum of two people accompany the transfer of a critically ill patient in addition to the staff required to operate the transport vehicle. The decision to transfer a critically ill patient is usually shared between the critical care consultants at the referring and receiving hospitals in collaboration with their consultant colleagues in the relevant specialities. Continuous monitoring of the ECG, SpO2 blood pressure and ETCO2 should be maintained throughout the transfer and recorded on the patient transfer sheet.