Factors for predicting the prognosis of myelodysplastic syndromes (MDS) have been widely used over the last few years. The proportion of bone marrow blasts, number and severity of cytopenias, and cytogenetic abnormalities are the main prognostic factors and can be used in combination to determine prognostic scores capable of predicting the outcome with fairly high accuracy. Molecular biology parameters, such as RAS and p53 mutations, can also be of assistance in establishing a prognosis. Factors that predict responsiveness to therapy are usually the same as those that predict survival. Current prognostic scores are unable to identify the minority of patients who will have very long survivals and therefore require no treatment.