Purpose. Determining the prevalence of and possible reasons for nonattendance of diabetic nutritional care clinics. Methods. Data were collected by means of a telephone survey and a review of patient records among 293 (166 attendees and 127 nonattendees) patients undergoing outpatient treatment at a university hospital. The t-tests, chi-square tests and logistic regression analysis were used to identify potential determinants of nonattendance. The theoretical framework was primarily based on the Health Belief Model. Results. In univariate analysis, nonattendance at the clinic was associated with a number of factors such as not visiting other care givers, risk perceptions, body-mass index, self-rated health, health locus of control, satisfaction with the dietitian, feelings of obligation to attend, and beliefs about the effectiveness of the treatment. In multivariate analysis only health locus of control and obligation to attend the visit were significant predictors of attendance. A significant number of respondents further reported that they perceived their visits to the dietitian to be of little use. Conclusion. One in three diabetic patients undergoing outpatient treatment skipped one or more visits to their dietitian. Patient education to improve attendance should focus primarily on convincing patients that they can contribute to their own health, and may stress the obligation the patients have when making an appointment with the dietitian.