Aim: To assess breastfeeding practices using the World Health Organization/United Nations Children's Fund (WHO/UNICEF) Ten Steps to Successful Breastfeeding for Baby-Friendly Hospitals in unselected non-UNICEF certified German hospitals and to examine the influences of breastfeeding promotion on long-term breastfeeding success as assessed by WHO criteria. Methods: Information on the fulfilment of the Ten Steps was collected in 177 randomly chosen maternity hospitals by a postal questionnaire. Breastfeeding duration was assessed in 1487 mothers delivering in these hospitals. Multiple logistic regression was used to estimate the association between a low breastfeeding promotion index, defined as fulfilment of fewer than five steps, and the risk of short-term breastfeeding, less than 4 mo. Results: A higher breastfeeding promotion index was not associated with early breastfeeding but was significantly associated with full breastfeeding at 4 and 6 mo. After adjusting for confounding factors, delivering in a hospital with a low breastfeeding promotion index was associated with an increased risk of short-term breastfeeding [odds ratio (OR) 1.24], although associations with maternal demographic variables (young age: OR 3.34), low educational level (OR 2.81) and upbringing in East Germany (OR 2.27) were stronger. Conclusion: In unselected German hospitals even moderate levels of breastfeeding promotion identified by WHO/UNICEF criteria were associated with long-term breastfeeding success.