The term "human milk banking" refers to the collection storage and processing of human milk donated by lactating mothers for infants other than their own. Much emphasis has been placed on attainment of intrauterine growth rates for infants of low birthweight somewhat at the expense of the therapeutic effects of human milk and the biological importance of human milk for the intrauterine to extrauterine transition. Antibody effects of human milk and apparently also of banked human milk are proven and would be especially indicated in the case of premature infants deprived of transplacentally acquired antibodies. The validity of the intrauterine growth model to estimate nutritional requirements may be diminished by the possibility that tissue accretion by low birthweight babies is different. Nutrient quality of human milk is less questionable than quantity. Human milk was banked at Oxford by some use of pumps and hand expression but with principal emphasis on drip breast milk (DBM secreted by the contralateral breast during feeding and usually wasted) as being a source least likely to deprive the donors infant a consideration that also precluded paying of donors. Milk is frozen and pooled diluting environmental contaminants but increasing risks of infection not existent in the case of a mothers breastfeeding her own infant. Pasteurizing processes which destroy microorganisms without reducing nutritive/antibody benefits are elusive: the Oxford project now uses a 30 minute 56 degree Centigrade cycle which eliminates the need for constant bacteriologic screening. Centrifugation ultrafiltration and freeze-drying have enabled Oxford scientists to manipulate protein us. Energy content of human milk to adapt it to varied nutrient needs at different infant growth stages.