In an attempt to characterize the prognostic significance of the main clinical and hematological features of chronic myelomonocytic leukemia (CMML), 30 such patients were allocated the "modified Bournemouth score". The most significant separation of groups predictive of poorer survival was obtained by setting a cutoff at the median score value for the whole series (score,2). On this basis patients could be divided into two different groups whose survival probability as well as risk of acute transformation significantly differ each other (P less than 0.05). In our opinion, this score could be of interest in treatment planning of CMML patients when the possibility of conservative or aggressive approach in envisaged.