Clear cell sarcoma of tendons and aponeuroses is a rare disorder which originates from migrated neural crest cells. It tends to local recurrences and dissemination and the prognosis has to be considered as poor. Based on a small series of patients, a wide surgical excision of the primary tumour or amputation are the therapies of choice. Radiotherapy might be of some value as an adjuvant treatment but radiotherapy and chemotherapy are of little value in the treatment of the advanced disease. Because of the lack of treatment alternatives we treated a 40-year-old female patient with disseminated clear cell sarcoma with interferon-alpha 2b (IFN-alpha 2b) perilesionally after several courses of systemic chemotherapy and radiotherapy had failed. After 4 months of therapy the patient came into a complete pathological remission which lasted for 17 months. A relapse of round cell sarcoma on both tumour sites was then noted. This outcome shows that IFN-alpha 2b was able to induce a complete remission in clear cell sarcoma and might have altered the natural course of the disease. IFN-alpha should be studied as adjuvant therapy after surgery of primary clear cell sarcoma and as a first-line palliative treatment in disseminated disease.