Outpatient departments lie at a critical interface between primary care and acute services. Increasing pressure to ensure efficient and effective health care delivery has resulted in outpatient departments investigating ways to minimise the number of patients failing to attend their scheduled clinic appointments. Failure to attend (FTA) is an expensive and persistent problem worldwide with rates of between 5-39% reported in the literature. Similar FTA rates have also been detected in the Australian context. This study was undertaken to further investigate the reasons for FTA by conducting a prospective comparison of 100 patients who attended their outpatient appointment with 100 patients who did not attend. Discriminant function analysis revealed that the major reason for non-attendance was the patients' opinion about the difficulty in getting to the hospital. Previous non-attendance was found to be the strongest predictor of future FTA behaviour. A number of operational and system recommendations are made that based on the results, which may assist management to develop interventions to improve attendance rates.