Business Rules
Citibank
Aside from the initial scope document, one of the most important documents in any project is the business rules document. This document is what establishes the characteristics of what should happen when a user accesses the application or site and what features are available to that user. The document doesn't detail all logic within the system but outlines the general understandings of how it should work.
The business rules document for the Citibank project includes security information, a graphical style guide, a use case, data information, general top level information as well as detailed information on specific processes and data transformations. In this case the document has probably outgrown the boundaries of what a Business Rules document should be, but since the project never had its own use cases or style guides outside of this document it proved to be useful.
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