Business use cases help to test development of a new system or enhancements to an existing system against requirements. After finalizing scope, one can identify business use cases to simulate the different conditions under which external actors may use the system. Business use cases act well as a way to capture business requirements. Use cases should act at a high level rather than an .
extremely granular level to avoid coming up with an exploding number of use cases for testing. Two different use cases should be separated though if they have different priorities or work through different iterations.
Business use case descriptions should state the source and the target, i.e. "what" the users do with the system. To successfully define a use case, one should define the actors, the goal, the pre-conditions, the post-conditions, the main flow, the exceptions, and the alternate flows.
More Reference Links: http://www.ibm.com/developerworks/rational/library/dec04/behrens/ http://www.iag.biz/white-papers-templates/business-analysis-resources/7-steps-to-writing-business-use-cases.html
