This report describes an automated method of unit test design based on requirements specified in a subset of the statechart notation. The behaviour under test is first extracted from the requirements and specified in the Z notation. Existing methods and tools are then applied to this specification to derive the tests. Using Z to model the requirements and specify the tests allows for a deductive approach to verifying test satisfiability, test result correctness and certain properties of the requirements. An examination of the specification coverage achieved by the tests is provided and the report concludes with an evaluation of the work to date and a set of directions for future work.