This chapter describes the standard equipment and monitoring components of the cardiopulmonary bypass (CPB) machine and extracorporeal circuit as well as additional equipment such as the suckers used to scavenge blood from the operative field, cardioplegia delivery systems and hemofilters. The tubing in the CPB circuit interconnects all of the main components of the circuit. The arterial cannula is used to connect the arterial limb of the CPB circuit to the patient and so deliver oxygenated blood from the heart-lung machine directly into the patient's arterial system. Venous cannulation for CPB allows deoxygenated blood to be drained from the patient into the extracorporeal circuit. The Terumo CDI 500 in-line blood gas analyzer is an optical fluorescence and reflectance based in-line system that continuously monitors 11 critical blood gas parameters with laboratory quality accuracy. Non-invasive simultaneous arterial and venous saturation monitors are also available for use during CPB.