Abstract: Compensation of pressure driven leakage while using high precision volumetric pumps may be provided. A measurement apparatus comprising a pump may be calibrated. Calibrating the measurement apparatus may comprise creating a characterization of leakage through the pump as a function of a pressure difference over the pump. The measurement apparatus may be operated for a predetermined time period to pump a liquid. A measurement of a flow through the measurement apparatus may be determined based on the amount of rotation of the piston. The measurement of the flow may be compensated for leakage of the pump while the measurement apparatus operated for the predetermined time period based on the characterization of leakage and the amount of piston rotation during the period and the monitored pressure difference over the pump.