Recurrence of carpal tunnel syndrome following surgery is not rare. The reported frequency of reoperation varies from 0.3 to 12%. We distinguish between persistent carpal tunnel syndrome, and recurrent carpal tunnel syndrome which we define as reappearance of the condition three months or more following surgery. More proximal nerve lesions or other erroneous diagnoses may cause either persistent or recurrent syndromes. In the cases of persistent syndromes, incomplete division of the flexor retinaculum is a frequent cause, but iatrogenic nerve lesions or active flexor tenosynovitis may also be to blame. In the cases of recurrent carpal tunnel syndrome, the problem is often due to perineural fibrosis. At the time of reoperation, except in those cases where an incomplete division of the flexor retinaculum is found, one must consider whether or not to combine the neurolysis with an additional procedure to prevent or diminish recurrent fibrosis. To achieve this goal, a number of measures have been proposed, including interposition of a biomaterial or raising a local flap to surround and protect the nerve. Others recommend early mobilization to diminish fibrous adhesions between the nerve and surrounding tissues. The results are at best modest, and may be counterproductive after several interventions. It is necessary to distinguish between improvement in symptoms that are due to local irritation, the priority for the patient, and improvement in neurologic function of the motor and sensory components of the nerve. According to the literature, from 43 to 90% of patients who undergo repeat operations continue to have symptoms, and one in five get no relief, while 80% of first operations for carpal tunnel syndrome give excellent results. These findings indicate that the first intervention must be performed with the most rigorous attention to technical detail.