Purpose: The trainings for teachers’ professional development were planned and implemented by the Ministry of National Education (MoNE) for a long time in Türkiye. The MoNE has improved the teachers’ professional training system in late 2021 considering the teacher needs, school autonomy and recent research results on effective training policies. This study aims to evaluate the results from the first year of new approach via teacher participation and satisfaction data. Design/Methodology/Approach: The study is design as a casual-comparative research. The teacher population data from the last five years to evaluate the participation and satisfaction within comparative approach. The participation and satisfaction are measured via official participation data and teacher training survey by MoNE. Findings: Results show that the new approach led a great boost in both the total- and individual participation in 2022. The improvement in participation reflected in all ISCED levels. The gender- and seniority distribution have become more balanced. Teachers’ satisfaction has maximized in all aspects of trainings in 2022. Highlights: The new approach by MoNE has led a great increase in the participation: almost all teachers in Turkish education system participated the in-service trainings. New approach considering teacher needs and flexibility have a substantial potential for developing the teachers’ professional development.