Abstract. In the academic milieu, several persistent problems often challenge the teachers' self-efficacy in optimizing education for sustainable development (ESD). This empirical pursuit aims to scrutinize a comprehensive best-fit model that explains the complex relationship between the transformational leadership style of school heads, teachers' attitudes, teachers' participation in professional development, and teachers' self-efficacy in education for sustainable development. SPSS v.26 and AMOS software were used to evaluate 400 valid cases in a quantitative descriptive-correlational predictive research design utilizing structural equation modeling. After stratification of the hypothesized models based on the analysis and theoretical relevancy, Model 3 was the best-fit model to divulge the predictive link among transformational leadership of school heads, teachers' attitude, and teachers' self-efficacy in ESD, which affirms the theory of Social Cognitive Theory. The result suggests transformative leadership and fostering positive attitudes are crucial in enhancing teachers' self-efficacy in the ESD context in promoting advancement to prioritize the accessibility and equitability of quality education while bolstering lifelong learning opportunities, as conveyed in SDG (Sustainable Development Goal) 4.

Keywords: Self-efficacy; Transformational leadership; Teachers' attitudes; Education for Sustainable Development (ESD); Structural Equation Modeling (SEM).