Aim: The aim of the study was to describe infant feeding practices and associated factors, and to explore mothers' main reasons for starting and stopping breastfeeding. Methods: We performed a national inquiry into milk feeding practices among 9133 Dutch infants aged <7 mo by means of a questionnaire. Results: 78% of mothers initiated breastfeeding. At 1 and 4 mo, respectively, 51 and 25% of infants were fed primarily on human milk; after 6 mo, only 15% of mothers still provided human milk as the only source of milk feeding. During the whole 6-mo period, another 11 to 18% was fed on both breast and formula milk. Women initiating breastfeeding were more likely to be higher educated, have a higher-educated partner, be non-smokers, have a full-time job, and be primipareous. In addition, breastfeeding initiation rate was higher for women born outside the Netherlands. Longer duration of breastfeeding was mostly found amongst higher-educated, non-smoking women. The odds for continuation of breastfeeding after 4 mo increased when mothers' working hours did not exceed 16 h/wk. Infant delivery at home was associated with a higher initiation rate as well as longer duration of breastfeeding compared to hospital delivery. Infants born after ≥38 wk of gestation, with a birthweight of ≥3500 g had higher odds to be breastfed for a longer period. Conclusion: Only a minority of Dutch infants is breastfed for 6 mo. Maternal and infant characteristics are important predictors of breastfeeding initiation and duration. © 2005 Taylor & Francis Group Ltd.