Conclusions1. Dogs survive for prolonged periods, at least 57 days, following reversal of their hepatic venous circulation. 2. Crimped teflon vascular prostheses remain patent in these low pressure venous systems and function satisfactorily enough to achieve objectives of this experiment. 3. This experimental preparation is presented as one potentially capable of contributing materially to studies of hepatic function and intrahepatic and extrahepatic vascular hemodynamics.