Abstract: A volumetric infusion pump for intravenous administration of fluid to a patient, including a volumetric cassette for receiving fluid from an IV fluid container and for pumping such fluid at a controlled rate using an IV administration set until a predetermined volume of fluid has been infused into the patient. The volumetric cassette contains, when filled, a predetermined volume of fluid. The cassette, when coupled to a driving mechanism in the pump, provides for the fluid to be pumped from the cassette at a predetermined rate. Once the cassette chamber has been at least partially emptied a predetermined amount by the operation of the pump, the volumetric chamber of the cassette is rapidly filled and the pumping continues with such emptying and filling of the cassette chamber alternately occurring until the predetermined volume of fluid has been pumped. The cassette is of a syringe type having a chamber and a plunger piston and the stroke of the plunger is controlled by the driving mechanism of the pump.