A study was conducted to examine four proposed underlying factors in eating disorders; locus of control, self-esteem, positive and negative affect levels, and perception of body and self (actual and ideal). Two groups of participants were asked to volunteer. Firstly, an experimental group, i.e. eating disorder participants (ED participants), and secondly, a control group, i.e. non-eating disorder participants (non-ED participants). All participants were given a questionnaire booklet containing five questionnaires in total. Four questionnaires examined each of the above factors and the fifth was designed to collect some background information and give participants an opportunity to make any additional comments if they so wished. It was predicted that there would be significant differences in participants scores of each factor depending on whether they were in the experimental or control group. Two predictions, concerning self-esteem and positive affect levels, were supported. Results for locus of control and negative affect levels were not significant. Due to the problematic nature of the grid-form questionnaire designed to measure perception of body and self, these results did not lend themselves to statistical analysis. These results are discussed in terms of how they can further our understanding of how an eating disorder functions in a person's life, with a view to understanding the practical implications for treatment. Some methodological issues are raised and proposals for future research are highlighted.