This study aims to explore the role of educational supervision in the sustainable professional development of teachers in government schools in Kuwait. Employing a descriptive methodology, which is deemed most suitable for this research, the study utilized a structured questionnaire as the primary research tool. The questionnaire consisted of two parts: the first section gathered demographic data, while the second assessed the role of the school principal in the sustainable development of teachers. The survey was administered to a random sample of 248 school teachers in government schools.

Study Results:
High Perceptions of Supervisory Practices: Teachers reported high levels of satisfaction with the modern supervisory practices implemented by school principals.
Positive Views on Professional Development: Teachers expressed positive perceptions regarding professional development opportunities, highlighting their effectiveness and relevance.
Lack of Demographic Differences: The study found no statistically significant differences in perceptions based on gender, years of service, educational qualifications, or specialization.
Strong Correlation with Professional Development: A strong positive correlation was identified between the implementation of modern supervisory practices by school principals and the professional development of teachers in government schools.

Recommendations:
Training for School Principals: Conduct training sessions focused on modern supervisory practices to enhance the effectiveness of school principals in government schools.

Professional Development Enhancement:
Implement strategies to qualify and empower school principals to promote sustainable professional development for teachers.

Comparative Studies:
Replicate this study in private education schools to facilitate a comparison of results between public and private sectors.

Incentive Programs:
Establish financial and moral incentive programs for school principals who effectively adopt and apply modern supervisory practices.

Performance Monitoring Committees:
Form committees tasked with regular follow-ups to evaluate the impact of supervisory practices on school performance and teacher professional development.

Keywords: Educational supervision, School development, School principal, Government schools.