Transformational versus transactional leadership styles and project success: A meta-analytic review

Despite the fact that the reliance on project teams and project-based organizations has significantly increased over the past decades, previous meta-analyses paid no attention to the examination of leadership styles in the context of projects. The purpose of this study was to meta-analytically synthesize and investigate the contradictory evidence on the effects of transformational leadership and transactional leadership on project success. The study also examined several project-level and country-level moderators in such effects. The study used 64 effect sizes from 41 primary studies on projects to examine the proposed relationships. The findings suggested that transformational leadership had a stronger effect on project success than transactional leadership. The results further indicated that project-level factors (i.e., project size and project type) moderated the relationships of leadership styles with project success. Moreover, the country-level factors (i.e., power distance, collectivism, and economic status of the country) also moderated some of the relationships. Theoretical and practical implications are provided in the end.