-the specifications are used to create JUnit3 TestSuite and TestCase objects -however, since TestSuite is not an interface, a JUnitSuite trait is used to represent it (and the JUnitSuite uses a TestSuite internally to hold the tests) -a specification is represented as a JUnitSuite -a system under test (sus) is represented as an ExamplesTestSuite <: JUnitSuite -an example is represented as an ExampleTestCase <: TestCase Then, the JUnitSuite which implements the junit.framework.Test interface can be run using a custom JUnit4 annotation: JUnitSuiteRunner This JUnitSuite trait encapsulates a JUnit3 TestSuite to allow it being seen as a trait and not a class The suite is initialized once whenever some information is required, like getName, or countTestCases