OBJECTIVES: The Behavior Rating Inventory of Executive Function (BRIEF) is the most widely used questionnaire developed for parents and teachers of school-age children to assess executive function behaviors of children and adolescents in the school and home environments. It is composed of 86 items organized in eight clinical scales (Inhibit, Shift, Emotional Control, Initiate, Working Memory, Plan/Organize, Organization of Materials, Monitor) and two validity scales (Inconsistency and Negativity). It is used to evaluate children/adolescents (5-18 years old) with a wide spectrum of developmental and acquired neurological conditions. The objective of this study was to develop the BRIEF in four Balto-Slavic languages (Bulgarian, Latvian, Lithuanian and Serbian) and one Uralic language (Estonian). METHODS: The following methodology was used: (1) Clarification of concepts with the developers; (2) Forward/backward step: two forward translations by native translators, reconciliation of the forward translations; one back-translation by an English-speaker fluent in the target language, and review by the developer. RESULTS: The translation process did not reveal any cultural issues since most of the concepts assessed were cross-culturally relevant. The main difficulties consisted in finding conceptual equivalents of the original items with strong idiomatic content. For instance, the most problematic items were items 18, 55 and 71. Item 71 [Lies around the house a lot (“couch potato”)] raised difficulties because of the expression “couch potato” which had to be removed in most of the translations. The intended meaning (the child loafs around the house, lying on the couch, doing nothing productive) was rendered in all target versions. Deletion of this expression in the original US version was also discussed with the developers. CONCLUSIONS: The cross-cultural adaptation of the BRIEF into Balto-Slavic and Uralic languages required an international collaboration. The involvement of the developers during the whole process enabled the production of conceptually equivalent and culturally appropriate measures.