Gilles de la Tourette syndrome is a chronic neuropsychiatric disorder that can have a detrimental impact on the health-related quality of life of children with the condition. To date no patient-reported health-related quality of life measures have been developed for children and adolescents in the English language. This study validated the first disease-specific scale for the quantitative assessment of health-related quality of life in 118 children and adolescents with Gilles de la Tourette syndrome (C&A-GTS-QOL) following language adaptation from Italian to English in the United Kingdom. Standard statistical methods were used to test the psychometric properties of the rating scale. Principal component factor analyses led to the identification of six health-related quality of life domains (cognitive, copro-phenomena, psychological, physical, obsessive-compulsive, and activities of daily living), explaining 66.7% of the overall variance. The C&A-GTS-QOL demonstrated satisfactory scaling assumptions and acceptability; validity was supported by interscale correlations (range 0.2-0.7), confirmatory factor analysis, and correlation patterns with other rating scales and clinical variables.