In this paper, representations of Spanish Secondary Education trainee teachers (n = 163) are analyzed with regard to the socio-environmental problematic, end-purposes, and strategies of education for sustainable development (ESD). Likewise, the study seeks to identify the potential influence of sociodemographic variables on those representations and, in particular, possible differences between either the perceptions or the beliefs of trainee teachers of Geography and History and those from other disciplines. The study can be classified as a non-experimental ex post facto investigation based on a questionnaire, yielding results that reflected the commitment of the students towards teaching through the implementation of strategies directed at conflict resolution for social transformation, and towards teaching the development of critical and creative thinking skills for social interventions. Likewise, the study reports the promotion of specific socio-educational actions leading to sustainable development. These results show the absence of differences in terms of the sex, age, institutional affiliation, background discipline or specialism, or previous training in Sustainable Development Goals (SDGs) of the students. Despite the identification of greater tendencies towards the conceptualized development of social awareness and active citizenship among trainee teachers of Geography and History, these results reflected the pertinence and the educational need for ESD in higher education from a holistic and transversal perspective.