Principle of Unity of Command implies one subordinate-one superior relationship. Every subordinate is answerable and accountable to one boss at one time. This helps in avoiding communication gaps and feedback and response is prompt. Unity of command also helps in effective combination of resources, that is, physical, financial resources which helps in easy co-ordination and, therefore, effective organization.
For eg: In an organization ,Managing Director has got the highest level of authority. This authority is shared by the Marketing Manager who shares his authority with the Sales Manager. From this chain of hierarchy, the official chain of communication becomes clear which is helpful in achievement of results and which provides stability to a concern. This scalar chain of command always flow from top to bottom and it defines the authority positions of different managers at different levels.