This study explores the critical role of effective leadership in achieving success in project management across diverse organizational contexts. As global competition and project complexity increase, leadership has emerged as an indispensable factor that complements the technical and procedural aspects of project management. The research examines the interrelationship between project management frameworks and leadership theories, emphasizing how classical, contemporary, and transformational models contribute to project performance. Through a comprehensive review of literature and empirical findings from 2015–2023, the study identifies key leadership traits such as emotional intelligence, adaptability, ethical integrity, and strategic communication as vital determinants of project success. It highlights how transformational leadership fosters innovation, motivation, and trust, while transactional and situational approaches ensure discipline and efficiency. Moreover, the study underscores the importance of transparent communication and team motivation in enhancing stakeholder satisfaction and performance outcomes. Effective decision-making, risk mitigation, and the ability to manage change are also found to be core leadership competencies that drive project resilience. Case studies further demonstrate that projects led by communicative, ethical, and adaptive leaders achieve higher success rates than those lacking strong leadership direction. Overall, this research concludes that effective leadership transforms project management from a technical process into a collaborative, human-centered practice that ensures sustainability, innovation, and long-term organizational success.