The essential functions that a school is called to perform within the framework of compulsory education vary under the influence of the prevailing conditions. However, beyond the specific needs of each era and location, a core mission of the school is to ensure, on the one hand, high student performance and, on the other hand, equality in the distribution of opportunities for all students.

Specifically today, schools are tasked with fulfilling these functions while considering the challenges of our time, such as multicultural coexistence, the dominance of technology, the evolution of sciences, and the rapid renewal of knowledge. At the same time, the goal of the school is not only to prepare students for the present but also for a continuously changing future.

The aforementioned characteristics of the modern school significantly determine the role of the educator, who must possess the necessary qualifications and professional knowledge. This raises the question What qualifications must educators have to be effective in their work. It is neither feasible nor appropriate to definitively and absolutely outline these qualifications, given the fluid nature of teaching and the complexity of the educator's role.

However, a temporary recording of these qualifications is a necessary prerequisite for both designing teacher training programs and establishing criteria for the selection, evaluation, and self-evaluation of educators. This book addresses - utilizing modern discussions and primary research findings - the issue of professional knowledge of educators. The purpose of the research was to delineate the content of pedagogical studies, as derived from the needs and assessments of active educators. A subsidiary goal was to systematically record the pedagogical knowledge that is assessed for the selection of educators in order to enter the profession in Greece.