The early recognition of perioperative coagulation disorders is essential to identify non-surgical reasons of bleeding, to initiate appropriate haemostatic treatment and finally to reduce perioperative blood loss. Conventional laboratory coagulation tests include prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen levels and platelet counts. Although these parameters are frequently assessed, their value has been challenged at least in the setting of acute perioperative bleeding [1]. PT and aPTT are performed in an artificial ‘in vitro’ system, i.e. in plasma separated from whole blood, which is then warmed to 37 C and buffered to a pH of 7AE4. These standardized conditions often do not reflect the patient’s situation [2]. Plasmatic ‘in vitro’ tests merely reflect the time elapsing until the activation of thrombin, but provide only marginal information about the functional state of the coagulation system (e.g. platelet function, interaction of plasmatic coagulation factors with platelets and red blood cells, clot firmness, fibrinolysis). Routine coagulation tests are mostly performed in the central laboratory, i.e. remote from the operating theatre. As a consequence, test results are often not available in time or with a considerable delay [3]. Current devices designed for point-of-care (POC) monitoring of coagulation have been designed for the assessment of coagulation directly at the bedside, so that results could be available earlier. Moreover, POC tests are usually performed in whole blood, thereby comprising interactions between cellular components (i.e. platelets and red blood cells) and plasmatic coagulation factors. Commonly used POC devices for assessment of plasmatic coagulation and platelet function are listed in Table 1. This review focuses on rotation thrombelastography (ROTEM ) as a global coagulation test and multiple electrode aggregometry (MEA, Multiplate ) for assessment of platelet function. Rotation thrombelastometry (ROTEM )