This paper presents a methodological solution to a main challenge quantitative research has to meet: The construction of measurement equivalence. Using an international research project investigating future teachers’ career choice motives, the paper demonstrates a validation approach for scales obtained from confirmatory factor analysis across countries. Measurement invariance analyses provide information on whether cross-country differences result from cultural bias, misconceptions or mistranslations during the construction of the instrument. Thus, the methodological approach helps to ensure the validity of quantitative transnational research by incorporating the demand for comparability into the instrument. The results show country specific differences among future teachers’ career choice motives that can be linked to different political and social framework conditions, including the appreciation of altruistic motives, working conditions or the universities’ content structure of their teacher training programs.