This review highlights the recent research on the use of prophylactic platelet transfusions, which is a topic that still provokes controversy. Over the last 12 months, there have been several studies with important new findings.Two randomized controlled trials compared different doses of prophylactic platelet transfusions in patients with haematological malignancies. In neonates, platelet mass has been used as a trigger for prophylactic platelet transfusions rather than the morning platelet count; and interim results of a therapeutic vs. a prophylactic platelet-transfusion strategy in acute myeloblastic leukaemia have been published.Low-dose prophylactic platelet transfusions are as effective in the prevention of bleeding as high-dose platelets. Fewer platelets were transfused but more frequent transfusions were required. Platelet mass as a transfusion trigger led to a lower prophylactic platelet requirement and did not increase the risk of bleeding in thrombocytopenic neonates. The interim results of the trial of a therapeutic vs. a prophylactic transfusion strategy were unable to provide any firm conclusion about their relative effectiveness and further information is required from ongoing trials.