Fiedler's Contingency Theory (1967) states that there is no single best leadership style. Leadership effectiveness depends on the fit between the leader's style and situational favorableness, which is determined by three factors:

1. Leader-member relations — degree of trust and respect
2. Task structure — degree to which the task is clearly defined
3. Position power — formal authority of the leader

In nursing management, a Head Nurse must adapt leadership style to the situation. Task-oriented leaders perform best in very favorable or very unfavorable situations; relationship-oriented leaders perform best in moderately favorable situations.