BACKGROUND The promotion and maintenance of breastfeeding with late preterm infants (LPIs) remain under examined topics of study. This dearth of research knowledge, especially for this population at-risk for various health complications, requires scientific investigation. In this study, we explore the experiences of mothers and the perceptions of public health nurses (PHNs) about breastfeeding late preterm infants in Calgary, Alberta, Canada. METHODS We used an exploratory mixed methods design with a convenience sample of 122 mothers to gather quantitative data about breastfeeding. We collected qualitative data by means of individual face-to-face interviews with 11 mothers and 10 public health nurses. Data were collected from April 2013 to June 2014. We then employed an interpretive thematic analysis to identify central themes and relationships across narratives. RESULTS We collected 74 complete data sets about breastfeeding. During the first 6-8 weeks postpartum, 61 mothers breastfed their infants. Of these, 51 partially breastfed and 10 exclusively breastfed. For qualitative purposes, the researchers interviewed 11 mothers with late preterm babies and three themes emerged: significant difficulty with breastfeeding, failing to recognize the infant's feeding distress and disorganized behavior, and the parental stress caused by the multiple feeding issues. The public health nurses' comments reinforced and expanded on what the mothers reported. The themes for the nurses included: challenges with initiating breastfeeding, challenges during breastfeeding, and the need for stimulation during breastfeeding. CONCLUSIONS Mothers face challenges when breastfeeding their late preterm infants and public health nurses can guide them through this experience. Families with a late preterm infant need to be informed about the challenges associated with breastfeeding a late preterm infant. It is necessary for all health care professionals to receive proper training on safe and effective breastfeeding of late preterm infants. It is essential for public health nurses to communicate effectively with families of late preterm infants to provide anticipatory guidance about potential challenges and strategies to resolve any breastfeeding problems.