The CBM system has enabled our laboratory to measure breast growth and demonstrate the importance of the short-term local control of milk synthesis in lactating women. Although the specific mechanism by which the short-term control of milk synthesis occurs has yet to be fully understood, it is now apparent that the interaction between storage capacity, degree of fullness, and frequency of milk removal plays a significant role. These factors demonstrate that the breastfeeding mother can take comfort in the individuality of her breast development and feeding pattern, which is uniquely adapted to suit the physiology of her breasts and the developmental requirements of her infant.