Organizations are growing in terms of size and geographical coverage, thereby increasing the workload of executives. To cope up with this workload, managers should delegate routine activities to their subordinates. Delegation of such activities would leave managers free to handle key strategic issues. The number of subordinates a manager has to supervise has a direct bearing on the degree to which managers can interact with and supervise subordinates. The span of control refers to the number of subordinates a superior can supervise efficiently and effectively.
According to Kathryn M. Bartol and David C. Martin, “The span of management or span of control is the number of subordinates who report directly to a specific manager.”
The principle of span of management states that there is a limit to the number of subordinates a manager can effectively supervise, but the exact number will depend on the impact of underlying factors.
One important thing is to be noted in the definition cited above. It is not how many people who report to a manager that matters. What matters is how many people who have to work with each other report to a manager. What counts are the number of relationships rather than the number of men.
The span of control is a very important principle that emphasizes the need for coordination among the subordinates working under a particular manager. The question therefore arises: how many people can a manager supervise effectively? Students of management have come to the conclusion that a manager can effectively manage usually four to eight subordinates at the upper levels, and eight to fifteen subordinates at the lower levels. According to the British consultant, Lyndall Urwick, the ideal number of subordinates for a higher level executive should be four while the number of
subordinates for an executive at the lower level may be eight or twelve. Others are of the view that a manager can manage twenty to thirty subordinates.