Pulsed radiation generated by powerful neodymium glass lasers was used to treat 272 cases of stage I skin melanomas; 250 patients were treated 5 years ago or earlier. Local recurrences of melanoma were detected in 2 cases within 1 to 8 years of follow up. Regional metastases developed in 45 cases and distant ones in 12 female patient presented with a transport metastasis. In patients treated 5 years ago or earlier, regional metastases occurred in 16.2 +/- 3.8 percent cases, distant ones in 4.4 +/- 1.6 percent, and transport ones in 0.4 percent. Five-year survival was registered in 84.5 +/- 2.8 percent of patients. Powerful pulsed laser radiation is effective in treating flat and slightly elevated skin melanomas that are up to 4.5 cm thick and that are characterized by levels I to IV of invasion.