The present invention enables a component under test to bind to a single component, that is capable of simulating most depended upon services, including the details of their interface, whether or not they return explicit results or cause side effects, and regardless of the state of their implementation. This invention includes features that allow for dynamic reconfiguration to meet the needs of both manual and automated testing, including the ability to control normal and exceptional results, as well as features to support both unit and integration testing.