The role of principals has been changed because of the rapid growth in technology, the different expectations of the stakeholders and diversity in education. The current education system of Pakistan assigns a routine role to school principals where they are not capable enough to meet all the expectations of stakeholders and the challenges posed to them by the global world. There appears timely need to modernize the education system of Pakistan. It is the principal's vision, instructional supervision, leadership skills and managerial practices that appear more conducive to ensure the overall effectiveness of the school. They should be innovative, progressive and productive in their performance.These dimensions of their interventional roles were not adequately explored in research and now warrant a proper study to identify the areas in which principals' interventions bring fruitful results. The emphasis of this study was on government girls' high schools in Peshawar city, Khyber Pakhtunkhwa Province of Pakistan.This effort is dedicated to my parents and family.