The management of Jehovah's Witnesses can prove quite challenging to the surgeon who routinely uses blood and blood products in the treatment of anaemia and hypovolaemia. The medical and legal dilemmas are exacerbated when the patient has a critically low haemoglobin level or has suffered life-threatening blood loss following polytrauma. It is essential that the treating physician should have some knowledge and understanding of the beliefs of the Jehovah's Witness in order to effectively minimise and treat blood loss. This paper reviews the ethical and medicolegal aspects involved, as well as alternatives to allogenic blood products in the treatment of anaemia in the polytrauma Jehovah's Witness patient.