Das et al demonstrate that rFVIIa (blue) promotes hemostasis by binding to the endothelial protein C receptor (red), promoting the cleavage of protease-activated receptor 1 (black line), and inducing the release of procoagulant extracellular vesicles (tan circles) from endothelial cells. These vesicles localize into growing clots, bind factor VIIa, and promote the activation of factor Xa and thrombin.