This study showed that children and adolescents with inflammatory bowel disease (IBD) had a more external locus of control than did matched diabetic and healthy children. An external locus of control correlated with severity of physical illness and presence of psychiatric disorders. It also correlated significantly with family dysfunction, which was found to be more common in the IBD group than in the groups compared. Tendencies toward a tense and negative family climate were observed in the IBD families. Awareness of the interaction between physical and psychosocial factors in IBD is essential in the management of therapy.