Cardiopulmonary bypass (CPB) and extracorporeal membrane oxygenation (ECMO) serve as vital extracorporeal circulatory technologies. This chapter concisely overviews both technologies, with a focus on pediatric CPB management. CPB core components include roller/centrifugal pumps, membrane oxygenators, and temperature-modulated circuits. Key aspects of CPB management emphasize adult-pediatric distinctions in flow parameters and temperature control, perfusion flow adjustment by body metrics, ACT-guided heparin titration, anesthesia management, hemodilution targets, ultrafiltration, α-stat/pH-stat blood gas management, deep hypothermic strategies, and protamine reversal. ECMO uses simplified circuits with centrifugal pumps and oxygenators to offer medium-to-long-term cardiopulmonary support with veno-venous mode for respiratory support and veno-arterial mode for cardiorespiratory support. While CPB facilitates surgical intervention, ECMO sustains critically ill patients during recovery, both demand meticulous anticoagulation and monitoring. Despite risks like bleeding and thrombosis, these technologies remain pivotal in modern cardiac and critical care.