Significant programmatic experience and research evidence regarding HIV and infant feeding have accumulated since recommendations on infant feeding in the context of HIV were last revised in 2006. In particular, evidence has been reported that antiretroviral (ARV) interventions to either the HIV-infected mother or HIV-exposed infant can significantly reduce the risk of postnatal transmission of HIV through breastfeeding. This evidence has major implications for how women living with HIV might feed their infants, and how health workers should counsel these mothers. In light of this, the World Health Organization (WHO) commenced a guideline development process, culminating in a Guideline Development Group meeting in Geneva on 22–23 October 2009. The process was carried out as outlined in the WHO handbook for guideline development.