The incidence of melanoma has increased more rapidly than any other type of cancer. In this review, we summarize the most important genetic alterations that contribute to the development of malignant melanoma. Our knowledge of the genetic and biological events involved in the genesis and progression of this disease has been benefited from the evolvement of a wealth of genetically engineered animal models. Hopefully, the understanding generated by all these studies will contribute to develop new therapeutic strategies to handle this fatal malignancy.