The purposes of the present investigation are to compare the structure and level of multidimensional self-concepts for boys and girls from England and Australia, and to demonstrate the use of confirmatory factor analysis (CFA) in making such comparisons. Subjects were random samples of 303 English preadolescents and 303 Australians that were matched in terms of age and sex. In the first set of analyses, CFA demonstrated that an a priori factor structure of self-concept fitted responses by English and by Australian students, and that the factor structure was reasonably invariant across the two groups. In the second set of analyses CFA demonstrated that English and Australian students differed significantly on only one of eight self-concept factors, and that all sex differences in the multidimensional self-concepts were similar for English and Australian students. The results of the study provide further evidence of the generality of multidimensional self-concepts as inferred by the Self Description Questionnaire, and demonstrate recent advances in the application of CFA. (Author)