In patients with malignant melanoma elective regional lymph node dissection (ELND) is controversial. This retrospective study evaluated differences in prognosis in patients who were treated with or without ELND. 168 patients were included who initially presented with stage I melanoma (without palpable regional lymph nodes), and who had a minimum observation period of at least 5 years, or had died of malignant melanoma within 5 years of diagnosis. In 66 patients a wide local excision (WLE) followed by ELND was done. In 102 cases only a WLE was done. Assignment of patients to the two groups was non-random but there was no significant difference in age, sex, type and location of primary tumour and depth of invasion. No significant difference was found in survival of the two groups. The 5 year survival of the WLE group was 85.7% and that of the WLE plus ELND group was 89.1%. The 10 year survival rate was 77.9% and 73.1%, respectively. Neither in the whole series nor after sub-division of the patients into three classes according to Breslow depth of invasion (up to 1.5, 1.51-2.5, and greater than 2.5 mm) was a significant influence of ELND on the survival of patients apparent. Cox's regression model did not show ELND as a prognostic factor. ELND cannot be recommended as a routine treatment in patients with stage I melanoma.