This article had four goals. First, the authors identified a set of general challenges and questions that a life-span theory of development should address. Second, they presented a comprehensive account of their Motivational Theory of Life-Span Development. They integrated the model of optimization in primary and secondary control and the…

Using Fiedler's Contingency Model of Leadership Effectiveness, which postulates that the behavior of a leader depends on the interaction between leadership style and the degree to which the environment gives the leader control and influence, a study investigated the effects of training and changes in position power on the behavior of three types…