Extension has many opportunities to promote breastfeeding, one of the most highly effective preventive measures a mother can take to protect the health of her infant and herself. This article describes how and why Cooperative Extension can and should partner with federal and state efforts to promote breastfeeding. Members of Rutgers' Family and Community Health Sciences department served on state work groups to identify and implement evidence-based strategies for promoting breastfeeding in health care, child care, and work site settings. Extension is an important public health partner, providing technical assistance, content expertise, and resources that meet the needs of communities.