The aim of this paper is to review the thrombogram and its use for phenotyping the haemostatic system. The thrombogram can be readily obtained through Calibrated Automated Thrombography (CAT), using a commercially available fluorometer, dedicated software (Thrombinoscope (R)) and a calibrator. Here we explore the possibility to use platelet-rich plasma (PRP) triggered with a low amount of recombinant human tissue factor (similar to 0.5 pM) and also explore the function of the protein C system by adding activated protein C (APC) or soluble recombinant thrombomodulin (TM). Examples are shown: inherited antithrombin (AT) and protein C deficiencies, and antiphospholipid antibodies. (c) 2004 Elsevier Ltd. All rights reserved.