Work Product (Artifact): Use Case
This artifact captures the system behavior to yield an observable result of value to those who interact with the system.
Purpose

Use cases are used for the following purposes:

  • To reach a common understanding of system behavior
  • To design elements that support the required behavior
  • To identify test cases
  • To plan and assess work
  • To write user documentation.
Relationships
Description
Brief Outline

A use case typically includes the following information:

  • Name: The name of the use case
  • Brief Description: A brief description of the role and purpose of the use case
  • Flow of Events: A textual description of what the system does in regard to a use case scenario (not how specific problems are solved by the system). Write the description so that the customer can understand it. The flows can include a basic flow, alternative flows, and subflows.
  • Key scenarios: A textual description of the most important or frequently discussed scenarios
  • Special Requirements: A textual description that collects all of the requirements of the use case that are not considered in the use-case model, but that must be taken care of during design or implementation (for example, non-functional requirements)
  • Preconditions: A textual description that defines a constraint on the system when the use case starts
  • Post-conditions: A textual description that defines a constraint on the system when the use case ends
  • Extension points: A list of locations within the flow of events of the use case at which additional behavior can be inserted by using the extend-relationship
Properties
Optional
Planned
Illustrations
Tailoring
Impact of not havingWithout this artifact, it might be unclear which functionality the solution needs to support.
Reasons for not needingYou might not need to use a use case if your project uses alternative requirements practices (for example, “The system shall…” statements).
Representation Options

You can document the use case as a use-case specification document or you can incorporate the use case in a use-case model. You can also use a requirements management tool to capture use cases and parts of use cases.

More Information
Checklists
Concepts