Fifteen one-year old infants with oesophageal atresia and their parents were used to demonstrate how the Parent-Child Early Relational Assessment (PCERA) can be used to explore the mother-child interaction in a clinical sample of children. The infants and their mothers were videotaped for 5-min episodes during feeding and free play, and the quality of the mother-infant interactions was assessed by PCERA. The results showed areas of strength regarding most of the maternal, infant and dyadic components. There was concern about maternal positive physical contact, maternal quality of verbalizations to or about the child, maternal social initiative, infant's communicative competence and infant's visual contact with mother. This concern of social proximity between infants and their mothers was most prominent in the feeding situation. The present study indicates that oesophageal atresia in infants may constitute stressors impinging on the parent-infant relationship. PCERA was found to be an adequate assessment tool with acceptable reliability to evaluate the mother-infant interaction.