In an attempt to answer the question of what influences mothers' decisions on how to feed their babies, a questionnaire was administered to 200 mothers when their babies were approximately 1 year of age. The questions covered a wide variety of factors, including socio-economic, educational, housing and family details, employment, ante- and perinatal experiences, maternal beliefs, support systems and actual feeding practices. Those mothers who had breast-fed their babies for longer than 36 weeks were compared with those who had stopped before 12 weeks. The most important factors distinguishing the two groups, as decided by stepwise regression analysis, were the beliefs that breast-feeding helps teething and does not make the baby irritable; also female babies were more likely to be breast-fed and the postnatal income of the mother was important. It is believed that these factors, together with the other, less statistically significant differences, should be used when formulating breast-feeding promotion strategies. The importance of income, and therefore of employment, underlines the necessity for legislation requiring large-scale employers of women to provide crèches and breast-feeding breaks for female staff.