We administered the Gender Identity Interview for Children, a 12-item child-informant measure, to children referred clinically for gender identity problems in Toronto, Ontario, Canada (N = 329) and Amsterdam, The Netherlands (N = 228) and 173 control children. Confirmatory factor analysis identified a Cognitive Gender Confusion factor (4 items) and an Affective Gender Confusion factor (8 items). Patients from both clinics had a significantly higher deviant total score than the controls, and the Dutch patients had a significantly higher deviant score than the Toronto patients. In this cross-national study, we are the first to report on the validity of this measure to discriminate children with gender identity disorder from controls outside of North America.