The evolution and professional development of teachers has been a major issue for the field of education in recent years. The last three years due to the Covid-19 pandemic, alongside its negative consequences, also had positive results, since the importance of the continuous development and professional development of each employee was highlighted in order to respond effectively to the rapidly evolving conditions.

The teachers' immediate and effective adaptation to the new pedagogical and teaching conditions imposed by the Covid-19 pandemic highlighted their will to progress in order to provide better quality educational work to their students. In the last four (4) years after the emergence of the Covid-19 pandemic, the need for the modern worker (and in this particular research, the modern teacher) is to constantly evolve in order to respond to the rapid developments in all sectors and to be effective and efficient. The provision of quality and effective learning "forces" the modern teacher to follow developments and modern data and they in fact must be a partner of changes and innovations at all levels.

This specific research seeks to highlight the positive aspects of the teacher's development through the European program Erasmus+ KA2, using as a sample teachers of school units in the Region of Western Greece. Specifically, the opinions of a sample of 106 Primary and Secondary education teachers of school units in the Region of Western Greece, who have implemented at least 1 Erasmus+ KA2 program, were studied. The data collected, through a structured questionnaire, were analyzed statistically and results were extracted through the statistical package SPSS n. 27 and statistically significant conclusions were reached regarding the contribution of the implementation of Erasmus+ KA2 programs to the teachers themselves, in terms of their professional development and improvement, while at the same time particularly important future career prospects emerged.

Keywords: Erasmus + KA2, education quality, teacher's professional development.