Cutaneous melanoma is a significant and increasing clinical problem. Knowing accurately the prognosis in a given patient is critical for treatment decisions and for optimal patient education. In this article we discuss the most current information regarding prognostic factors in early-stage and advanced malignant melanoma. Tumor thickness and ulceration are the most important predictors for primary melanoma. Number of positive lymph nodes is the most powerful predictor for stage III patients, and sites of disease and lactase dehydrogenase levels are the most useful predictors in metastatic disease.