For many years , experts on leadership focused their attention on what has become known as the trait theory of leadership. It rests on the idea that leaders possess certain physical or psychological characteristics that enable them to "stand above the pack." For example, a person as a leader might be tall, intelligent , or achievement oriented.
This approach often concentrated on historical figures like Napoleon and Caesar. Experts concluded that leaders were born, not made. While a few experts give some credence to trait theory, no definitive list of essential characteristics exists, leading to a declining interest in the topic. The few lists that do exist are value laden.
Nevertheless, the work of Edwin Ghiselli and Ralph Stogdill has provided some useful insights. They look at two categories of traits: personality and motivational. Personality traits include intelligence, initiative, self-assurance, and others; motivational traits include needs for financial reward, self-actualization, and power. They attempt to associate these traits with characteristics like supervisory ability, achievement, intelligence, honesty, and self-confidence and determine that leadership ability is associated with judgment and verbal ability. They conclude, however, that a person could not be associated with a specific set of traits. 
Interestingly, if one trait seems to stand out under contemporary leadership studies, it is that a leader's effectiveness depends on whether he or she is people oriented. Some common characteristics of leaders include being expressive, honest, trustworthy, warm, and cooperative. Leadership effectiveness tends to decline, however, with characteristics like being aloof, impersonal, and cautious. 
 James H. Donnelly, James L. Gibson, and John M. Ivancevich, Fundamentals of Management , Business Publications, Inc., Piano, TX 1981, pp. 291 “294.
 Lorne Hartman, A psychological analysis of leadership effectiveness, Strategy & Leadership , p. 31, October-December 1999.