Breastfeeding makes a vital contribution to the health and development of babies, as well as to long term health. Establishing breastfeeding may not be easy even for mothers with healthy full-term babies. Mothers in the paediatric environment experience additional challenges: sick babies, delayed onset of breastfeeding and having to establish and maintain breastfeeding in situations where privacy may be limited and anxiety levels high. This first part of a two-part article describes the development of a breastfeeding support service in a tertiary children’s hospital. Institutional support, a dedicated post and a planned programme of training and education, with the development of specific resource materials, have resulted in a service that closely matches the expressed needs of mothers.