The concept of leadership has been studied for many years. However, there is currently no single definition of how it can be acquired and what results it should have. Research about leadership has undergone several eras, each of which focused on a different aspect of leadership. The Personality Era was the first step in defining leadership, and it tried to connect this term to notable people. Known as the so-called Great Man period, this era implied that to become a great leader, one had to copy other people who had proved to be effective managers. However, this task was hard to achieve since all these people were different and shared no single behavior pattern. Thus, the next step became the Trait Period and called for paying attention to particular traits. Once again, however, no single set of traits was determined. The Influence Era made progress in recognizing that leadership can be seen only through relationships, as opposed to a single-person position. The Power Relation Period tried to define leadership by identifying the amount of power a leader possessed. The Persuasion Period that followed focused more on the influence that the leader had on his or her subordinates. Then came the Behavior Era, which discussed leadership in the context of actions rather than personality or position. The Early Behavior Period emphasized behavioral traits over personal ones, while the Late Behavior Period proposed that workers required motivation and adequate working conditions. The era ended with the Operant Period, which viewed leaders as people who could change their employees’ behavior. The Situation Era extended the definition of leadership, claiming that true leadership is the result of a combination of environmental factors. In other words, a truly great leader could only emerge in the right place and at the right time. The Social Status Period proposed that leadership roles were already defined in society, and managers must target their behavior to those expectations. The Contingency Era made progress by recognizing all the previous conditions as required. Three theories emerged: the Contingency Theory, the Path-Goal Theory, and the Normative Theory. The first one focused on the situation, the second one proposed creating conditions for subordinates to reach goals, and the last one implied the importance of decision-making behavior. The Transactional Era proposed that the primary definition of leadership is in role division and the interactions between managers and subordinates. The Exchange Period offered the Vertical Dyad Linkage theory to explain how leader-subordinate work changed their relationships. The Role Development Period supported this idea but paid more attention to the specific roles of employees and their managers. The Anti-Leadership Era was an interesting time, as it doubted the very existence of leadership. The Ambiguity Period, which argued that leadership is a value created in the mind of each person, was followed by the Substitute Period, which claimed substitutes for leadership could be developed in the early stages. The Culture Era that came afterward tried to revive the concept of leadership, arguing that it is something defined by the whole org