The aim of the research is to determine whether the critical leadership styles perceived by teachers are predictive of school effectiveness. The predictive research pattern, one of the quantitative research patterns, was used. The study group of the research consists of 305 volunteer teachers working in public schools in Üsküdar district of Istanbul Province. Participant Information Form, School Activity Index and The Crıtıcal Leadershıp Style Scale were used in the study. The data were analyzed by making parametric tests. As a result of the research, it was revealed that teachers' perceptions of school effectiveness did not make a significant difference according to their gender, educational status, years of seniority, and school level. Also, it was determined that teachers' critical leadership style perceptions did not make a significant difference according to their gender, educational status, years of seniority, and school level. Another important result of the research is that there is a moderate and positive significant relationship between teachers' critical leadership and school effectiveness.
Leadership, Critical leadership, Effective school, School effectiveness