As anucleate cell particles, platelets do not lend themselves to analysis by traditional cell and molecular biology techniques. Moreover, while valuable information may be gleaned from studies of messenger RNA in platelets, the rapid events in platelets are not governed by or dependent on alterations in gene expression. In contrast, proteomics, the study of the protein complement of a genome, will have a major impact on platelet biology. It offers the opportunity to comprehensively describe the proteins involved in discrete elements of platelet function, from the subsecond events following platelet activation and adhesion through to platelet aggregation and granule secretion. As the function of every protein is understood and as the mechanisms that regulate protein modifications are unravelled, we will discover a wealth of proteins that are themselves potential therapeutic agents or novel targets for the development of diagnostics and drugs. Here we review the current applications of proteomics to platelet research. We briefly describe various proteomic approaches to unravel platelet biology, including the documentation of platelet proteins, the investigation of thrombin-activated phosphotyrosine signaling networks and the analysis of the proteins that are secreted upon platelet activation. Proteomics is a young field and there are only a handful of published examples applying proteomics to platelet research. This number will increase over the next few years, as advances in analytical methods allow a more functional analysis of the platelet proteome.