The 'Guideline melanoma of the skin, second revised consensus' was published in March 1997. Some of the contents are cited: Over 1600 new melanomas are diagnosed in the Netherlands each year; by now the mean 5-year survival amounts to over 80%. In examination of a pigmented lesion a dermatoscope is a valuable tool. The recommended margin of the diagnostic excision was reduced from 5 mm to 2 mm of macroscopically normal skin round the lesion; the margins in definite excision are: 1 cm of normal skin for a Breslow thickness < or = 2 mm; 2 cm for a Breslow thickness > 2 and < or = 4 mm. A margin of at least 2 cm seems also justified for thicker melanomas. Elective (prophylactic) regional lymph node dissection is advised against. Sentinel node biopsy appears to be an attractive method to detect occult metastasis in regional nodes. In lymph node metastasis a (therapeutic) regional lymph node dissection should be performed. In case of inoperable tumourgrowth in an extremity regional isolated perfusion is indicated. Radiotherapy may be applied curatively (e.g. if surgery is not possible), palliatively (if desired in combination with hyperthermia) or postoperatively (if non-radical resection is suspected). Adjuvant systemic therapy in melanoma patients is still experimental; the earliest results of high doses of interferon alpha are encouraging. Atypical (dysplastic) naevi and congenital naevi are important risk factors for melanoma. No consensus was reached regarding prophylactic removal of all congenital naevi. Regarding the duration of the follow-up period, 5 years suffices in patients with a melanoma with a Breslow thickness < or = 1.5 mm (provided there are no histological signs of regression), while 10 years is required for melanomas with a Breslow thickness > 1.5 mm. The patient should be actively involved in the follow-up (inspection, palpation). Routine blood testing, roentgen examination or ultrasonography are considered to be useless. There are no indications that hormonal alterations during pregnancy or use of the pill stimulate the growth of micrometastases that may be present. Excessive exposure to ultraviolet rays is discouraged.