Environmental education (EE) has an important educational background in Greece as it appears in its precursory form in the 1980s. EE gradually, through international initiatives, shifted to education for sustainable development (ESD). This alteration of EE to ESD made ESD an educational current that has been constantly enhanced over the last decade. Due to its holistic character, ESD is compatible with the latest educational approaches. This was expected to lead to the implementation of ESD in the Greek education system without obstacles, something that did not happen as even today there is inertia regarding its introduction. The purpose of the paper is to analyze attitudes and perception on introducing sustainability issues on educational system based both on theoretical and empirical analysis. In particular, the theoretical analysis aims to identify the absence of ESD from the Greek education system and records the lack of the term sustainability from the school textbooks. For the empirical analysis, a questionnaire is used in order to estimate the perceptions of secondary teachers that apply different educational approaches to ESD as well as their desire to integrate it into their teaching. We conclude that teachers consider the lack of resources, materials, or intangibles ones and the absence of training as major obstacles hampering the implementation of ESD. Educators identify obstacles to the implementation of ESD due to their own practices and attitudes, as well as due to issues outside the school context. The study supports the view that the structural integration of ESD in the school curriculum is of great importance as it will lead students to sustainable attitudes and behaviors.