A method of controlling and regulating a transmission brake which, for the purpose of synchronization, determines a target rotational speed of a shaft to be synchronized on the basis of an actual rotational speed of a transmission shaft, and controls a transmission brake such that the determined target rotational speed is set for the shaft that is to be synchronized. The transmission brake also carries out additional functions. These functions require no, or only minimal, additional hardware complexity in a cost-neutral way, but considerably increase the functional and practical value of the transmission brake. The comfort and speed of shifting operations, the protection or, as the case may be, the detection of error states in sensors, a clutch, a main clutch or a motor control are improved, and undesirable transmission states avoided. It is also possible to account for and influence other conditions, such as the operation of ancillary devices.