By taking users' needs as their starting point the authors avoid giving a specialised coverage of just one method and instead concentrate on the main methods and techniques used in constructing a self-tuning system. The structure reflects the different aspects of a self-tuning system - identification algorithms, controller algorithms and signal processing. To enable a fundamental understanding basic algorithms and techniques are explained without too much theoretical rigour. Applications and commercial instruments which involve self-adaptive methods are also discussed intensively and recent research is documented to provide background information.