The field of melanoma biology has experienced a remarkable surge in recent years, owing to progress which has ranged from the most basic laboratory/preclinical discoveries to clinical developments that have begun to transform the management and prognosis for at least certain melanoma patients. Among the key areas that have contributed to this progress are studies relating to signaling and transcriptional pathways that regulate control over differentiation and survival of the melanocyte lineage. The identification of recurring activating mutations in specific signaling factors (B-RAF, N-Ras, c-KIT), amplification of other melanoma oncogenes (MITF, NEDD9), and the crucial recognition that certain of these genomic events occur within melanomas arising with specific clinical features (eg mucosal or acral origin) have led to clear recognition that melanoma is indeed "many different diseases.� While the various subclasses of melanoma may share common features, such as profound invasive and metastatic propensity, it is also likely...