Considerable effort is spent in the design and testing of disc brakes of modern passenger cars. This effort can be reduced if refined mathematical–mechanical models and new experimental techniques are used for studying the dynamics of these brakes. The present paper is devoted to the modelling and the active suppression of brake squeal. A four degree of freedom disc brake model is described and its behaviour with respect to the variation of important parameters is analysed. To actively suppress brake squeal, ‘smart pads’ were designed, manufactured and tested in our laboratory. These pads contain piezoceramic staple actuators, which can be independently driven at both pads and within the pads. Two different control strategies are described and tested on the basis of this model. The first control law is based on optimal control and includes a Kalman–Bucy filter to estimate the system's state. The second control law maximizes the energy dissipated by the friction forces between the disc and the brake pads. Both control strategies are compared with respect to their practical application and implemented in a floating caliper disc brake at a test rig in Darmstadt. Copyright © 2005 John Wiley & Sons, Ltd.