The purpose of this dissertation was to compare and contrast the Leadership Styles of two Heads of Department who work at Carnelian Secondary School (anonymized). It augments a previous paper (Parascandalo 2011) which examined the role of the middle leader in secondary schools in educational literature. The investigation by means of two case-studies aimed to establish similarities and differences in leadership styles and its intention was to discover how different leadership qualities and approaches promote specific aspects of management which can make a department more effective. The research was based on the following questions: 1. What does the literature of educational research and theory tell us about defining leadership styles? 2. What are the similarities and the differences between the leadership styles of the two studied Heads of Department? 3. What are the teachers' and the SMT members' perceptions of the leadership styles of the two studied Heads of Department and how do they react to them? 4. What kind of learning cultures are encouraged by each of the two studied Heads of Department to promote departmental team building? 5. What kind of programme of training for Heads of Department might be put in place to promote successful practices and effective management strategies? Participants included the two HoDs and all willing members of both teams, all the members of the SMT and two student teachers undertaking their practicum with one of the departments. Respondent triangulation was obtained through the perceptions of all the above, while methodological triangulation by means of interviews and observation sessions proved very valuable as ethnographic research to really understand how both teams functioned. Qualitative data was from the sampling of results. All institutions, locations and individuals were anonymized. Results suggest that Monica rarely moves out of the transformational style, has a high level of emotional intelligence and has a family bond with her members. In contrast, Catherine continually moves in and out of the transformational, transactional and the laissez-faire styles and has only a professional relationship with members. The similarities emerge when both leaders operate within the transformational leadership style while the differences emerge when Catherine frequently moves in and out of the three main styles identified for this study. It was concluded that, even though higher marks were obtained in Catherine's subject, the same students fared much better in Monica's subject as her papers demanded intellectual, logical and mental visualization abilities, while Catherine's paper, one size fits all, was mostly based on fill-in, multiple choice and picture interpretation exercises. Recommendations cover training in leadership, the organisation of resource sharing and a Human Resource position to identify and organise training for leaders. It is hoped that this investigation into leadership styles and their effectiveness will be followed by others as research in this area is limited in Maltese schools. The following are appended: (1) The findings and analysis of the perceptions of Thomas and Gary, student teachers in Catherine's department, regarding her leadership style; (2) The observation; (3) The sampling of students' results and outcomes; (4) Schedule of interview questions for HoDs; (5) Schedule of interview questions for teacher in department; (6) Schedule of interview questions for student teacher in department; and (7) Schedule of interview questions for the SMT. [The research work disclosed in this publication is partially-funded by the ESF project 4.100--Developing Core Skills in the Public Service. The sponsorship is partially-financed by the European Union, from the European Social Fund (ESF) under Operational Programme II--Cohesion Policy 2007-2013, "Empowering People for More Jobs and a Better Quality of Life".]