M.A. (Clinical Psychology) / The purpose of this study was to determine whether children who are diagnosed as having Attention Deficit Disorder (ADHD), and Geschwind's syndrome, show a tendency to greater allergic responsivity manifesting in a greater sensitivity to specific foods than a control group. In order to test out these predictions, it had to be assessed whether these children displayed differential sensitivity to the food groups of sugar, dairy products and artificial flavouring and colouring. It was also necessary to establish whether these children will show a decrease in levels of activity contingent upon withdrawal of a foodstuff to which a differential sensitivity has been demonstrated. The subjects participating in this study were rated on a Conners Rating Scale to assess the degree of hyperactive behaviour, by both parents and teachers over a six week period. The overall pattern of results indicated that children with a combined diagnosis of ADHD and Geschwind's syndrome would show a greater behavioural responsivity to certain foodstuffs, and contingent upon their withdrawal, show a significant decrease in hyperactive behaviour. It is proposed that the study be repeated utilising a larger sample.