Although Portugal has an equalitarian labour law, gender is still an important category in the citizens' participation among different professional domains. That is why social practices and cultural meanings that informs men' but mostly women' labour activities contradict national law. People who work in professional domains that do not fit in the hegemonic symbolic representations cross social and cultural borders. The social construction of gender categories is a central influence in person's constitution processes, structuring their personal, familial and professional life. This study aims to understand the conditioning elements for women' and men' entrance in professional domains connected to gender categories they don't belong within. Cultural elements are passed between generations thus informing people's social identity's, defining gender categories, relating activities to performances "suitable to women" or "suitable to men", making individuals become "natural performers" of particular tasks in specific social places (cf. Comas; Aguilar). Personal and professional formation lies in the acquisition of technical qualifications associated to their gender category, which inform their insertion in the labour market, their performance and progression. However, we can find multiple situations in which individuals come to enter in professional fields socially perceived as belonging to gender categories that are not theirs. This research aims to identify the processes which lead to that kind of situations, where people cross professional barriers imposed by social representations on gender categories. To achieve this objective analyses will be conducted among two professional groups whose actors are in a position of "gender nonconformity in occupations" (cf. Kimmel): men working in the support of educational and health services, and women in technical computing and electronics, in three Portuguese regions (northern, central and southern). Methodologically researchers...