Carpal tunnel syndrome occurs very frequently and results from synovial tissue proliferation caused by a variety of events. Morbidity can be determined by detailed neurological examination and treatment depends on the extent of the distal latency. During the operation it is important to pay close attention to the various nerves and to proceed as carefully as the individual situation requires. The success rate also depends on adequate aftercare and follow-up. In the case of Guyon syndrome, operation is always indicated, with the goal being decompression and to search for the cause of the compression. The results are also excellent.