The research study in this book examines the direct and empirical relationship between project managers? leadership styles, years of experience and critical success factors in relation to the measured project success. The research study presented in this book was proposed at the doctoral dissertation level and deemed scientifically necessary for evaluation in order to solve the research problem and to fill the gap that was lacking in literature. The significance of this research study is that it contributes to more in depth and better understanding about the key factors that relate to project success. This book can be beneficial to students, researchers, leaders, managers, team members, stakeholders, and business owners who are interested in learning more about the research topic and in the empirical data results provided in the book. In addition, with practical application, the results of the research study presented in this book can contribute to the improvement of project success rates across various business organizations and industries, provide justification for the improvement of training programs for project managers, and can serve as a base for further research study.