Example of an Expanced Case Description

Use Case: Exit Car Park
Actors: Employee
Goal: To successfully leave the car park

Overview:
When a member of staff wishes to leave the car park they drive to the exit barrier. The barrier senses the presence of the car, rises to allow the employee to drive through and lowers when they have gone. After this it adds one to the number of spaces available in the car park.

Typical Course of events

Actor Action____________________System Action
1. Employee arrives at exit barrier_____2. Barrier senses a car present
_____________________________3. Barrier rises
4. Employee drives away___________5. Barrier lowers
____________________________6. A space added to available number

Alternative courses:
3. The barrier malfunctions and does not rise (the employee seeks assistance and the barrier is opened for them by car park staff)