During the past century explosive developments have taken place in the field of molecular medicine and genetics, vastly expanding our understanding of the normal physiological response to injury. We have been able to characterise specific molecular and cell biological processes and apply some of this knowledge to the treatment of multiply injured patients. Despite the significant steps we have made, there still remains much work to be done in this area. This review article highlights the current concepts of post-traumatic immunological changes and their impact in the management of trauma patients.