Operations, information, systems, and contingency management Modern management theorists recognize that multiple management approaches are available and that not every approach can be used for every situation. At the same time, they realize there are commonalities in situations and that companies in similar situations will benefit from similar management practices. For example, in is book Theory of Leader Effectiveness, psychologist Fred Fiedler proposed that leaders use different styles in different situations to be effective. When situations were highly positive or highly negative, a task-oriented approach was best. On the other hand, when situations were somewhere in the middle, a relationship-oriented approach was best. Fiedler's theory and others like it are called contingency theories, and they imply that the most effective management technique