In the periperative setting, platelet diagnostics has following indications: positive bleeding history (inherited or acquired platelet defect; antiplatelet medication); extracorporeal circulation; unclear intra-/postoperative bleeding (after normal first-level tests; in the presence of factors that affect platelet function, e.g. colloids). New POC methods for platelet function assessment are available: Multiplate® (sensitive to COX-1 inhibitors and ADP-receptor antagonists; predictive of bleeding in cardiac surgery); PFA-100TM and Ultegra (sensitive to COX-1 inhibitors and GPIIbIIIa inhibitors); PlateletMapping Assay® (sensitive to COX-1 inhibitors and ADP-receptor antagonists). Following perioperative haemostatic interventions may be considered for improving platelet function: platelet concentrates, DDAVP, rFVIIa, fibrinogen concentrate, and antifibrinolytics.