Definition
Paul Hersey and Kenneth Blanchard in the late 1960s were the first to describe the directing leadership style. The directing leader clearly provides specific instructions, defines the roles and tasks of the "follower," and closely supervises task completion.
Decisions are made by the leader and announced to the followers, so this communication style is largely one-way.
Explanation
Along with Daniel Goleman, Hersey and Blanchard were advocates of conditional leadership. They believed no single style applied to all situations, and a successful leader would flex their leadership style to their operating environment.
The directing leadership style is most effective when the followers are relatively inexperienced, and need to be instructed in how to accomplish tasks. For example, when there is a large flow of new personnel into the organization, the directing leader should be very explicit when directing subordinates. Closely monitoring progress is also important, in case additional directions are required.