Objectives: A service evaluation project on the reasons why children do not attend their outpatient appointments. Design: Analysis of paediatric clinic lists over two consecutive days. Parents of the non-attenders were identified and their reasons for not attending the appointment were elicited using a survey. Setting: The appointments were scheduled to take place in the Paediatric department at St. Mary’s Hospital, London. Participants: Of the 201 appointments scheduled, 49 patients did not attend their paediatric appointment. Telephone contact was successful with 35 parents. Main Outcome Measures: Parents were asked to verify if their contact details were correct, if they were aware of the appointment and if they had received a reminder. The reasons for non-attendance were explored. Results: Of the 49 non-attenders, correct contact details were held on file for 24 of the patients (49.0%). Of the 35 parents contacted, 18 were aware (51.4%) of their child’s appointment. Conclusions: This project revealed that the principal reason for non-attendance is unawareness of the appointment due to incorrect contact details held by the hospital. Potential strategies for reducing non-attendance at this paediatric outpatient clinic include, developing a confirmation or reminder system and improved communication with parents. The creation of a new interface between hospitals and GPs would allow hospitals to access patient contact details held by GPs. It would also ensure that hospitals hold up-to-date patient contact details and that appointment details are effectively communicated to parents. The interface would automatically feed through any updated patient details, keeping hospital records current.