The relation between teacher professionalism in school and educational process and outcomes, teachers' job attitudes and feelings, and school organizational factors was investigated through a questionnaire survey involving 62 aided primary schools, 58 principals, 1,476 teachers, and 7,969 students of one sponsoring body. The findings show that teachers' professionalism at the school level is positively related to students' affective educational outcomes. In classroom management, teachers with higher professionalism tended to use more professional power, as perceived by students. Teachers in high-professionalism schools seemed to show more positive job attitudes and feelings, higher esprit, and less disengagement. Also, professionalism was strongly associated with school formalization, and all measures of principal's leadership. Furthermore, the stepwise multiple regression analysis showed that principal's human leadership, teachers' disengagement (negative), and school formalization were the strongest predictors of professionalism at the school level. The profiles of high-and low-professionalism schools were contrastingly different in terms of students' educational outcomes, classroom management, teachers' job attitudes and feelings, and school organizational factors. The findings strongly support the importance of teachers' professionalism in the professionalization of teaching and enhancement of education quality. Copyright © 1996 Islamia University of Bahawalpur.