Reactive Systems offers the Reactis testing and validation package for Simulink and Stateflow models. Reactis Tester generates comprehensive yet compact test suites from models. Reactis Simulator enables users to visualize test execution, track test coverage, and fine-tune Tester-generated tests. Reactis Validator automatically searches models for violations of user-specified requirements. Reactis for C Plugin offers white-box analysis of the C code portions of models (S-Functions and Stateflow custom C code). The tool integrates seamlessly with (and requires) Reactis.