Social marketing involves the application of commercial marketing principles to advance the public good. Social marketing calls for much more than health communications campaigns. It involves four interrelated tasks: audience benefit, target behavior, essence (brand, relevance, positioning), and developing the "4Ps" (product, price, place, promotion) marketing mix. The ongoing U.S. Department of Agriculture "Loving Support Makes Breastfeeding Work" campaign was launched in 1997 based on social marketing principles to increase breastfeeding initiation rates and breastfeeding duration among Special Supplemental Nutrition Program for Women, Infants and Children (WIC) participants. Since then there have been improvements in breastfeeding duration in the country, and the majority of WIC women now initiate breastfeeding. Breastfeeding in public places is still not well accepted by society at large, and any and exclusive breastfeeding durations remain exceedingly low. Lessons learned from "Loving Support" and other campaigns indicate that it is important to design social marketing campaigns to target the influential societal forces (e.g., family and friends, healthcare providers, employers, formula industry, legislators) that affect women's decision and ability to breastfeed for the recommended amount of time. This will require formative research that applies the social-ecological model to different population segments, taking and identifying the right incentives to nudge more women to breastfeed for longer. Any new breastfeeding campaign needs to understand and take into account the information acquisition preferences of the target audiences. The vast majority of WIC women have mobile devices and are accessing social media. The Brazilian experience indicates that making breastfeeding the social norm can be done with a solid social marketing strategy. This is consistent with the recently released "Six Steps to Achieve Breastfeeding Goals for WIC Clinics," which identifies the need for exclusive breastfeeding to become the social norm at WIC clinics and strongly recommends for these clinics to adhere to the World Health Organization Code of Marketing of Breast-Milk Substitutes.