This report provides a comprehensive analysis of leadership within Tesco Lotus, a hypermarket chain in Thailand. The report begins with a reflection on the author's personal leadership experiences, followed by an exploration of relevant leadership models and theories, including the Great Man Theory, Trait Theory, and Behavioral Theory. It then delves into the leadership approaches adopted in daily work, such as situational and behavioral approaches, and critically appraises the author's autocratic leadership style. The report also outlines professional development strategies for becoming a successful leader, including goal setting, public speaking, and problem-solving skills. Part two critically evaluates the degree of leadership behaviors within Tesco Lotus, focusing on areas like higher education student services, non-profit management, organizational management, and professional coaching. The report concludes with recommendations to improve ethical leadership behaviors within the organization.