The third approach in the Leadership studies is the Leadership Skill Approach. While the Traits Approach took into account the personality of the leader and the Style Approach the behaviour of the leader, the Leadership skills approach takes into account the knowledge and abilities that the leader has. A leader can learn certain skills and turn himself into a remarkable one. Although different in the focus, the Traits Approach and the Skills Approach, both center their attention in the leader, as its main purpose. Researchers have studied leadership skills and abilities for a number of years. However, there are two influential models. The first one is a model proposed by Robert Katz in 1955. The second approach is proposed by Michael Mumford and colleagues in the year 2000. These models can be seen as complimentary to each other, since they offer different views on leadership from the skills point of view.

In the model proposed by Katz in the Harvard Bussiness Review, titled "Skills of an Effective Administrator" from 1955, he recognizes three different abilities that a leader should have. These are:

• Technical Skills
• Human Skills
• Conceptual Skills

Katz argued that these skills are quite different from traits or qualities of leaders. Skills are what leaders can accomplish, whereas traits are who leaders are (Northouse, 2007, p.40). A technical skill is knowledge about and competency and proficiency in a specific work or activity. For example, to use certain computer software packages (for example, MS Excel or Access) is an advanced technical skill.

A human skill is one that enables to work with people. It is different from technical skills which has to do with working with things. These abilities help us to get along with people and to communicate and work within teams.

A conceptual skill are abilities to work with ideas and concepts. These skills enable us to understand and better decide the actions and measures that has to be taken in a particular field of work.

Based on his observations Katz stated that the level of importance of each set of skills (technical, human and conceptual) was directly correlated with the level that the person has in the organization.