The clinical availability of artificial oxygen carriers (AOCs) would result in profound alterations in transfusion medical practice. Rapid progress in the scientific and technological development of AOCs has advanced to a critical stage at which safe and effective alternatives to the transfusion of red blood cells are emerging. Haemoglobin- and perfluorocarbon-based oxygen carriers are under current clinical investigation. Artificial oxygen-carrying solutions, by virtue of their acellular structure, can be used to transport oxygen to ischaemic tissues that cannot otherwise be reached by cellular blood components. Organs awaiting transplantation can be preserved for a long time after perfusion with AOCs and tumour susceptibility to chemo- and radiotherapy is increased. The use of AOCs is therefore not confined to their use as red blood cell substitutes, but may find a wide spectrum of interdisciplinary applications.