Leadership is documented as a complex but critical issue for performance improvement in all organisations. Due to its rapidly changing organisational environment, leadership has gained significance to respond to emerging challenges of performance in university libraries. Therefore, this qualitative research examined the importance of leadership for effective performance in Australian university libraries. The study collected primary data from interviewing 18 chief librarians of Australian public sector university libraries from all states other than Tasmania and the Northern Territory. The primary data from interviewing chief university librarians were thematically compared and analysed against the existing literature and library reports. The study confirmed that no single leadership style fits all situations. The study also found the significance of mixed leadership style among chief university librarians in Australian University libraries and the importance of switching to appropriate leadership styles at the correct times combined with strategic thinking to address dominant issues. Also, the study discusses the barriers to effective library change management that leaders should be aware of and the importance of knowledge in business management for the university library to contribute to the changing higher education enterprise. Practical and theoretical implications are also provided, including the need for future research.