Although postpartum dyads frequently present to the emergency department, treatment of the lactating parent and breastfeeding child is often driven by medical misconceptions. Incorrect advice about continuation or cessation of breastfeeding for medical reasons can lead to maternal and infant harm. In lactation, demand begets supply; missing a feed can be detrimental to short- and long-term breastfeeding outcomes. The purpose of this Clinical Nurses Forum article is to argue the importance of appropriate care of the breastfeeding dyad in the emergency department setting and to interpret current evidence-based information on lactation for the emergency staff nurse. High-quality care for the breastfeeding dyad requires knowledge of lactation physiology, contraindications for breastfeeding, and safe medications and diagnostic procedures. The well-informed emergency nurse must advocate for evidence-based care of the breastfeeding dyad within the emergency department.