A significant number of people with type 1 diabetes do not attend their clinic appointments. This study investigated the reasons underlying this decision and explored possible service improvement strategies. This was a cross-sectional telephone survey among all patients with type 1 diabetes missing at least one appointment at a diabetes clinic between 1 October 2009 and 30 September 2010. Patients were asked two questions: why they did not attend the appointment and how attendance could be improved. The initial 'did not attend' (DNA) rate for all appointments was 17.6% (808/4595 appointments). Of these, the largest number were missed by patients (n=252) with type 1 diabetes. After excluding 79 patients no longer under the service, 126/173 (72.8%) were able to be contacted and answered the questions. Forgetting the appointment was the most frequent response (34.9%). Many patients advised not to send appointment reminder letters too far ahead of appointments (12.7%, 16) and to send a text message reminder (26.2%, 33) two weeks before the appointment. The findings suggest that there is a role for improving the administrative approach to patients' appointments, reminding patients in advance and improving communication between hospital staff and patients. Copyright © 2012 John Wiley & Sons.