A bona-fide synapse assembles as a consequence of the interaction between P-selectin and its counter-receptor on neutrophils, with clustering of activated β 2 integrins into membrane microdomains and reorganization of cytoskeleton components that control cell motility and phagocytosis. Actual engulfment of the tethered platelet depends on the recognition of phosphatidylserine and/or of phosphatidylserine-associated molecules. This event may have a physiologic role in the regulation of the hemostatic potential of circulating blood; conversely, a failure may contribute to persistent vascular inflammation and thrombosis.