Who should be interested in Use case?
Customers, who need to be sure that the system that is getting built is the one that they want.
Managers, who need to have an overall understanding of what the system will do in order to effectively plan and monitor the project.
Analysts, who need to describe and document what the system is going to do.
Developers, who need to understand what the system needs to do in order to develop it.
Tester， who need to know what the system is supposed to do so that they can verify that is does it.
Technical writers,who need to know what the system is supposed to so that they can describe it.
User-experience designers, who need to understand the users' goals and how the will use the system to achieve these goals.