Hospital and birth center practices significantly affect whether a woman chooses to start breastfeeding and how long she continues to breastfeed. Several specific policies and practices, in combination, determine how much overall support for breastfeeding a mother giving birth in a particular hospital or birth center is likely to receive. The recommended elements of care for lactating mothers and their babies are those that are required for a hospital or birth center to be designated as “Baby-Friendly.” These elements are: (1) Have a written breastfeeding policy that is routinely communicated to all health care staff; (2) Train all health care staff in skills necessary to implement the policy; (3) Inform all pregnant women about the benefits and management of breastfeeding; (4) Help mothers initiate breastfeeding within one hour of birth; (5) Show mothers how to breastfeed and how to maintain lactation, even if they are separated from their infants; (6) Give newborn infants no food or drink other than breast milk, unless medically indicated; (7) Practice “rooming in” – allow mothers and infants to remain together 24 hours a day; (8) Encourage breastfeeding on cue; (9) Give no pacifiers or artificial nipples to breastfeeding infants; (10) Foster the establishment of breastfeeding support groups and refer mothers to them on discharge from the hospital or clinic. The Baby-Friendly Hospital Initiative (BFHI) is a global program sponsored by the World Health Organization (WHO) and the United Nations Children’s Fund (UNICEF) to encourage and recognize hospitals and birthing centers that offer an optimal level of care for lactation based on the WHO/UNICEF Ten Steps to Successful Breastfeeding for Hospitals. In the United States, the nonprofit organization Baby-Friendly USA oversees this program. To be designated as “Baby-Friendly,” facilities undergo external evaluation to demonstrate that the facility meets all ten of the recommended elements of care. All types and sizes of birth facilities can seek the Baby-Friendly designation. Some states have several small Baby-Friendly facilities, others have only one or two large Baby-Friendly facilities, and still others have none at all. Because birth facilities vary in size and the number of annual births, measuring the effect of their maternity care and practices on public health requires more than just counting the number of Baby-Friendly facilities per state. Thus, the public health impact is assessed by using the proportion of annual live births in the U.S. that occurred at facilities that have earned the Baby-Friendly designation.