Autistic spectrum disorder (ASD) is a developing area for dietetic referrals. There is little published data on current dietetic practice. Some children with ASD are referred for gluten/casein free diet. The theory is that abnormal metabolites in the urine may be a result of incomplete breakdown of gluten and casein in the gut. There are some published open studies that support the efficiency of such a diet [Knivsberg et al. (1995) Scand. J. Educ. Res.39: 223; Lucarelli et al. (1995) Panminerva Med.37: 137; Whiteley et al. (1999) Int. J. Res. Practice3: 45] and also that there are many anecdotal reports that the diet helps some children. Aims and objectives This study aimed to audit the types of referral made to the dietetic service to identify key dietetic issues and to describe factors which may influence outcome/disease management. Methods Dietetic records were used to audit the referrals to the dietetic service over a 3-month period. Seven-day diet histories were assessed using computer food composition tables and topics of interest recorded against a draft protocol agreed within the profession. Results Requests for gluten-free and casein-free dietetic advice, and/or the management of food selectivity and dysfunctional feeding behaviour constituted the majority of referrals. In many cases, child's environment was rarely simple. Conclusions Despite the limitations of this small study, the findings suggest that the management of these referrals is highly complex. A dietitian's input should ensure that the nutritional adequacy of the diet is maintained or restored.