Development of a software system from existing components can surely have various benefits, but can also entail a series of problems. One type of problem is caused by a limited exchange of information between the developer and user of a component. A limited exchange and thereby a lack of information can have various consequences, among them the requirement to test a component prior to its integration into a software system. A lack of information cannot only make testing prior to integration necessary; it can also complicate this task. However, difficulties in testing can be avoided if certain provisions to increase testability are taken beforehand. This article briefly describes a new form of improving testability of, particularly commercial, components, the self-testing COTS components (STECC) strategy and explains in detail the STECC framework, which implements the necessary technical architecture to augment Java components with self-testability.