One of the reasons attributed to the continuous decline in student performance and low educational outcomes in public schools is the poor leadership displayed by many principals. Despite the fact that there are no stringent criteria for the appointment of school principals or prerequisite qualifications, principals do have the potential to lead and manage efficient and successful schools. In this paper, I argue that principals can develop exemplary leadership practices when subjected to sound training and professional development programmes. The Department of Education and Higher Education institutions have emphasised the importance of formal qualifications for enhancing career development programmes for practicing and aspiring principals in South Africa. Using questionnaires, I explore the perceptions of teachers and school management team (SMT) members of the leadership qualities exhibited by principals who acquired the professional qualification referred to as the Advanced Certificate in Education: School Leadership and Management (ACESLM). Findings revealed that leadership development for principals is crucial for school improvement because of active teaching and learning. Leadership capacity requires principals to participate with relevant stakeholders skilfully, and where there is high leadership capacity, instructional leadership develops into sound leadership practices.