Positive psychology theories have evolved during the past three decades and focus on positive, holistic, health-related concepts in psychology. Positive psychology approaches have also been used in leadership and organizational change studies. These approaches have evolved through positive psychology, movements and waves, such as positive psychology wave one (PP1.0), the second wave of positive psychology (PP2.0), and the last wave of positive psychology (PP3.0). In this entry, it is argued that the three waves of positive psychology are particularly important in deeply influencing leaders, leadership, and the organization by providing guidance through positive and constructive perspectives and role models. They also offer guidance on how to lead, especially on how to lead organizations with purpose and meaning. Consequently, positive aspects (PP1.0), both, positive and negative aspects (PP2.0), and systemic (PP3.0) aspects of positive psychology approaches should be integrated and provide constructive, holistic views on leadership and the organization. This entry provides an overview and insight on new discourses on the three waves of positive psychology, leaders, leadership, and the organization.