This article reports on a longitudinal qualitative study of the psychosocial factors influencing women's experience of breastfeeding. The findings illustrate the complex web of factors, both personal and environmental, that influence breastfeeding behaviour. The significance of breastfeeding derives from the fact that it, in concert with the arrival of a new baby, heralds significant changes in a woman's day-to-day life. Three major areas of change, in part precipitated by breastfeeding, were critical. These include changes in the amount of time available to the mother and the nature of the activities that fill this time, changes in a woman's body due to pregnancy and breastfeeding, and changes in the nature of a woman's personal needs. These changes constitute a substantial and often disconcerting shift in lifestyle. The article examines the potential consequences of these changes for the mother and the host of mediating factors that influence her response to them and hence to breastfeeding. The mediating factors include the personal and psychological factors related to the attitudes, values and character traits of the mother, baby, and those close to them. Others are structural factors such as the absence or presence of formal and informal support systems that range from paid maternity leave to community drop-in centres, educational programmes, and community parks. They also include the host of cultural factors that influence the ways in which individuals and society view breastfeeding.