Specifying the Negative in TDD

Test-Driven Development (TDD) is a process in which test are written up-front.  Typically these tests reflect the requirements and expectations of the stakeholders to the project, driving the creation of useful, valuable behavior.

Sometimes, however, the requirement given is about something the system should not do, and must not do for a reason that is critical to the business we seek to serve.  The question this presentation will address is this: How can you write a test about a behavior that the system must not do?