Patients with hypoproliferative thrombocytopenia are at increased risk of bleeding. The standard approach to prevent bleeding is to give prophylactic platelet transfusions at platelet counts of ¡Â10,000/ul, but the optimal strategy is unclear. Randomized controlled trials have explored the effects of prophylactic platelet doses on hemostasis, and other trials are investigating giving platelet transfusions only when bleeding is recognized; i.e., therapeutic platelet transfusions. In the PLADO study, a three-arm prophylactic platelet transfusion dose trial assigned patients to receive all their platelet transfusions at a median dose (2.2 x 1011 platelets/m2), lower dose (¨ö the median dose), or higher dose (2x the median dose). The primary outcome measures were hemostasis and post-transfusion platelet responses. Discussed will be the PLADO results and their implications for clinical practice, as well as the rationale, design, and preliminary results of an ongoing 'therapeutic only' versus prophylactic platelet transfusion trial.