Tumor staging of melanoma is a crucial step for estimating patient prognosis, deciding on therapy approach, and efficient collection, analysis, comparison and communication of scientific data across borders and research groups. Recently, the Melanoma Staging Committee of the American Joint Committee on Cancer (AJCC) has proposed a revision of the widely used melanoma staging system, using an evidence-based approach, to reflect the improved understanding of this disease. Important adjustments were made related to the role of mitotic rate as a prognostic factor, definition of N category and classification of all microscopic nodal metastases, regardless of the extent of tumor burden, and specifically including micrometastases detected by immunohistochemistry as stage III. These revisions are to be implemented by early 2010 and are likely to be adopted and incorporated in international guidelines. Within the updated AJCC staging system, sentinel lymph node biopsy (SLNB) remains a standard-of-care diagnostic procedure, widely accepted as an important prognostic tool. According to current recommendations, SLNB is routinely offered as a staging procedure in patients with tumors more than 1 mm in thickness. Beyond its prognostic value, the therapeutic benefit of this procedure in improving overall survival yet remains to be proven. This article reviews and discusses the new aspects and challenges of the current staging recommendations for melanoma.