Blood platelets are important components of hemostasis, contributing to healing of wounds by forming thrombi and to the initiation of repair processes. They are also involved, however, in the pathogenesis of life-threatening complications such as stroke or myocardial infarction. Following injuries to blood vessels, platelets adhere to the damaged vessel wall, resulting in the formation of vascular plugs and release of intracellular substances, which initiate repair processes. Genetic defects may result in dysfunction of the platelets, inducing bleeding diseases such as Glanzmann thrombasthenia and Bernard-Soulier syndrome (1). Platelets arise as fragments of megakaryocytes, and are anucleate. Hence only restricted synthesis of proteins from residual megakaryocyte and mitochondrial mRNA may be possible, and therefore genome and transcriptome analysis of platelets is a substantial challenge. The clinical relevance of platelet dysfunctions and increased knowledge of the intracellular processes involved, make analyses of platelet proteome potentially very valuable.