This book introduces the components and principles of the common ballast management systems. The working principles of different filtration, cleaning and sterilizing equipment are also introduced. The calculation norm of the construction design and the calculation method of simulation are described. Besides, different aspects of system management are analyzed. The principle of various detecting sensors, the hardware of control system and the design method of human–computer interface are respectively introduced. Last but not least, the maintenance and management of ballast water management system are described, mainly the maintenance and management of key components which composes the system.