Breastfeeding is a complex process influenced by different personal and social factors which will determine both the initiation and the resilience for its maintenance. The aim is to identify the beliefs and expectations of mothers concerning breastfeeding to determine the perception of their self-efficacy and the influence on the management of their babies' feeding. A qualitative study through semi-structured interviews was carried out. The sample size was defined by the saturation criteria. Twenty-two women participated, eleven were from an urban environment and eleven were from a rural environment. Mothers' knowledge of breastfeeding, their expectations of that process, their experience, and their strategies for overcoming problems associated with initiating, establishing, and continuing breastfeeding were influenced by the role of nurses and midwives in supporting their perception of self-efficacy. Likewise, maternity policies are important for the continuance of exclusive breastfeeding. This study shows the complexity of the initiation and establishment of breastfeeding and the existence of several social factors surrounding these moments. Furthermore, it demonstrates the importance and reference of nurses and midwives and the role of State maternity policies.