Purpose: Gluten-free diet (GFD) is the cornerstone of treatment in celiac disease (CD). Compliance to GFD is often compromised by psychosocial factors as well as emotional (e.g., depression, anxiety), cognitive (e.g., perceived competence), and interpersonal (quality of patient-physician relationship) characteristics. Drawing from a social psychological theory of motivation called Self Determination Theory (SDT) (Deci and Ryan, 1985, 1991), we assessed the relative magnitude of the relationship between these psychosocial processes and compliance to GFD in a sample of patients with CD. Methods: Subjects included members of the Western New York Gluten-Free Diet Support Group who completed a testing battery, including the Celiac Dietary Adherence Test (CDAT), the Depression Anxiety Stress Scale (DASS), the Celiac Disease Quality of Life scale (CD-QOL), and the Celiac Symptom Index (CSI). The assessment also included SDT measures that were found to influence motivation in a range of chronic conditions. These variables included the Perceived Competence for CD Scale (PCS), measuring feelings of competence to comply with GFD, the Treatment Self-Regulation Questionnaire (TSRQ-CD), assessing autonomous versus controlled motivation, and the Health Care Climate Questionnaire (HCCQ-CD), measuring perceptions of physician autonomy supportiveness. Statistical analysis included Pearson correlations to measure linear relationships and hierarchical linear regression to determine predictors of noncompliance. Results: Of 500 members who received questionnaires, 190 completed the questionnaires. We report data from the first 100 questionnaires. As hypothesized, there was a significant correlation between non-compliance and depression (r=0.58, p<0.001), and to a lesser extent to anxiety (r=0.41, p<0.001) and stress (r=0.44, p<0.001). Non-compliance also correlated strongly with reduced perceived competence (r=-0.67, p<0.001) and disease severity (r=0.66, p< 0.001). Moderate correlations were found between compliance and autonomous motivation (r=-.43, p<0.001) as well as quality of life (r=0.46, p<0.001). In the final model of the regression analysis, significant independent predictors of noncompliance were perceived competence (β=-0.45, t=-0.4.90, p<0.001) and depression (β=0.28, t=2.80, p<0.01). Conclusion: Compliance to GFD in celiac patients is associated with psychological distress, particularly depression, as well as motivation factors including perceived competence and autonomous motivation. Non-compliance is associated with increased disease severity and reduced quality of life. These preliminary findings highlight barriers to compliance that, if addressed, can optimize the therapeutic value of GFD for this challenging disease.