OBJECTIVE: To investigate the lived experiences of neonatal nurses, that is, what it is like to be a neonatal nurse after developmental care is introduced in the unit. METHODS: The study was designed as a qualitative interview study with a hermeneutic-phenomenological approach. Participants were seven neonatal nurses working in an 18-bed level 2 and 3 neonatal unit at a tertiary university hospital in Denmark. Developmental care was recently introduced in the unit, and parents spend many hours a day with their baby and stay overnight in guestrooms at the hospital. RESULTS: The essential theme of the phenomenon being a neonatal nurse is found to be 'walking the line between the possible and the ideal'. Five themes illuminate this essence. They are: 'being attentive to the infant and the mother-infant dyad', 'the body tells', 'time is everything', 'working in a quiet and caring, crowded and distressing space', and 'teamwork - demanding or smooth and helpful'. CONCLUSION: Introducing developmental care in a neonatal unit changes neonatal nurses' experiences of caring for infants and mother-infant dyads. The meaning of body, time, space, and relationships are decisive and deserve to be included in nurses' and nurse leaders' discussion about developmental and family centred neonatal care.