Ample evidence is available on the impact of health care practices and hospital routines and procedures on breastfeeding. Good practices enhance successful initiation and establishment of breastfeeding and contribute to increased duration, just as inappropriate practices, and failure to support and encourage mothers, have the opposite effect. In 1991 the World Health Organization (WHO) and the United Nations Children's Fund (UNICEF) jointly launched the Baby-Friendly Hospital Initiative, which aims to give every baby the best start in life by ensuring a health care environment where breastfeeding is the norm. The initiative is based on the principles summarized in a joint statement issued by the two organizations in 1989 on the role of maternity services in protecting, promoting, and supporting breastfeeding. To become truly baby-friendly, hospitals and maternity wards around the world are giving practical effect to the principles described in the joint WHO/UNICEF statement that have been synthesized into Ten Steps To Successful Breastfeeding. This summary of the rationale and scientific basis for the Ten Steps is presented in the light of cumulative experience demonstrating the crucial importance of these principles for the successful initiation and establishment of breastfeeding.