Extracorporeal liver support devices aim at improving the therapeutical options for liver failure. Numerous artificial and bioartificial devices have been tested to reduce the high mortality of this dynamic disease. In particular, the detoxification function of the liver should be upheld, by means of a number of different procedures, either until liver function is restored or until transplantation. Both purely artificial, machine-based procedures including different forms of dialysis and hemoadsorption as well as bioartificial procedures based on hepatocytes are being tested, as are different types of extracorporeal liver perfusion. This paper provides an overview of the different methods and devices and their clinical evidence in order to give a recommendation for the handling of the expensive devices. There is no current indication for the application of liver support devices outside of clinical studies at specialised centres.