Background: Functional impairment is a key feature of chronic fatigue syndrome (CFS) of childhood. Aim: To compare impairment, illness attitudes and coping mechanisms in childhood CFS and in other paediatric disorders. Method: Participants were 28 children and adolescents with CFS, 30 with juvenile idiopathic arthritis (JIA) and 27 with emotional disorders (ED). The measures used were interviews with children and parents, with detailed enquiry on impairment, including the Functional Disability Inventory (FDI), Illness Attitudes Scales (IAS), and Kidcope to measure coping styles in relation to common problems, illness and disability. Results: Children with CFS reported significantly more illness impairment, especially in school attendance, than those with JIA and ED. They had higher "worry about illness" scores on the IAS. On the Kidcope they named school issues (work, expectations, attendance) as illness- or disability-related problems more than the other two groups. Fewer CFS participants reported using problem solving as a strategy to cope with illness and disability than with other problems in their lives. More in the CFS than in the JIA group used emotional regulation to cope with illness and disability. Fewer in the CFS than in the ED groups used social withdrawal to cope with illness and self-criticism for disability, but more used resignation to cope with disability. Conclusion: Severe illness-related impairment, particularly through school non-attendance, and high levels of illness-related school concerns appear specific to CFS. CFS may also have characteristically high levels of generalised illness worry and particular styles of coping with illness and disability.