A total of 213 melanoma patients were checked perioperatively with a 5-MHz sonographic scanner in order to detect lymph-node metastases; they were also checked in the scope of tumor follow-up. Of the 415 sonographic results, the method yielded a 97% accuracy. The soundness of lymph-node sonography has been proved histologically and/or through clinical observation. Compared to the other diagnostic techniques available for checking surface and subsurface lymph-node groups, lymph-node sonography is an advantageous combination of diagnostic practicability, accuracy, economic feasibility, and patient acceptance. The possible therapeutic implications are also discussed in this paper.