The two most used instruments to assess masculinity (M) and femininity (F) are the Bem Sex Role Inventory (BSRI) and the Personality Attributes Questionnaire (PAQ). Two hypotheses will be tested: a) multidimensionality versus bidimensionality, and b) to what extent the two instruments, elaborated to measure the same constructs, classify subjects in the same way. Participants were 420 high school students, 198 women and 222 men, aged 12–15 years. Exploratory factor analysis and internal consistency analysis were carried out and log-linear models were tested. The data support a) the multidimensionality of both instruments and b) the lack of full concordance in the classification of persons according to the fourfold typology. Implications of the results are discussed regarding the supposed theory behind instrumentality/expressiveness and masculinity/femininity, as well as for the use of both instruments to classify different subjects into the four distinct types.