Summary. The diagnosis of bleeding disorders is strictly dependent on the presence of bleeding symptoms in the patient, but collection of the bleeding history and its interpretation still remains subjective. For this reason, questionnaires on bleeding history have been proposed, and validated as diagnostic tools by comparing data obtained from patients with normal controls. This effort had led, at least with respect to von Willebrand disease (VWD), to the establishment of criteria that allow discrimination of VWD carriers from normal subjects. Among the possible criteria, a promising one is represented by the bleeding score (BS), a quantitative index summarizing both the number of episodes and their severity. The BS has shown good sensitivity and specificity for the diagnosis of type 1 VWD and could be integrated in a full diagnostic algorithm that also accounts for laboratory and family data. Furthermore, the BS has been shown to be correlated with several biological variables, including VWF and FVIII:C levels, platelet function analyzer (PFA-100™) closure times, and platelet glycoprotein haplotypes. Thus, collection of the BS at the time of the diagnosis may be a useful addition in the evaluation of the bleeding patients for both the researcher and medical practitioner, although the latter should probably wait for the results of further validation studies before making more extensive use of BS as a diagnostic tool.