The predictive value of sentinel node status in skin melanoma was studied. Between August, 2, 1994 and February, 20, 1998, in Surgical Department of Masaryk Memorial Cancer Institute, Brno, 166 lymphatic regions were explored in 153 patients with 154 melanomas. We were not able to visit any other institute performing this procedure, so our beginning failure rate has been quite high, approx. 40% declining to final less than 3%. Lymphatic mapping was performed with the use of Patentblau V dye (BYK, Germany), injected preoperatively intradermally to the tumour or into the scar after nonradical removing of melanoma. Lyphoscintigraphy has been used in cases of dubious lymphatic spread, especially in trunk melanomas. Hand held gamma probe could not be used for unacceptable cost. From 143 identified sentinel nodes were 26 positive in 24 patients. From these patients 10 relapsed, with 6 locoregional and 4 distant recurrences. 2 Patients died. In 108 patient with negative sentinel node 3 recurrences occurred, one nodal, and two local, no distant metastases occurred till now. The incidence of positive sentinel nodes was growing with Breslow thickness. Extremely poor prognosis can be expected in patients with Breslow > 4.0 mm and positive sentinel node.