Antithrombotic Therapy begins with a chapter reviewing the pathophysiology and regulation of blood coagulation and thrombin activity, with helpful figures illustrating the various pathways. The chapter on antithrombotic agents, a rapidly evolving field with multiple novel agents undergoing phase 2 and 3 clinical trials, has expanded to include a section on the newly approved synthetic factor Xa inhibitor pentasaccharide, as well as a focused discussion on future anticoagulants that are under development, such as oral heparin and the oral direct thrombin inhibitor ximelagatran. Furthermore, the section on low-molecular-weight heparin (LMWH) has expanded to include tinzaparin as the newly approved LMWH for venous thromboembolic disease treatment. The chapter on thrombolytic agents (appropriately renamed fibrinolytic agents) includes information on the latest cardiology clinical trials, such as the Global Use of Strategies to Open occluded arteries (GUSTO)-V and the Assessment of Safety and Efficacy of a New Thrombolytic agent (ASSENT)-3 trials. These trials assessed the efficacy and safety of the third-generation fibrinolytic agents, especially in combination with the potent GPIIb/IIIa receptor antagonists as antiplatelet therapy. New information on outcomes concerning the safety and efficacy of platelet inhibition with clopidrogel in the setting of acute coronary syndromes (ACS) and percutaneous coronary interventions are presented vis-a-vis the Clopidogrel in Unstable Angina to Prevent Recurrent Events (CURE), PCI-CURE, and Do Tirofiban and ReoPro Give Similar Efficacy Trial (TARGET) trials. The rapidly evolving data concerning GPIIb/IIIa receptor antagonists, including new data from the GUSTO-IV trial in ACS, the GUSTO-V, the Abciximab Before Direct Angioplasty and Stenting in Myocardial Infarction Regarding Acute and Long Term Follow-up (ADMIRAL), and the European/Australian Stroke Prevention in Reversible Ischemia Trial (ESPRIT) studies, as well as pharmacodynamic results from the Global Outcomes in Lung Diseases (GOLD) study are presented. More importantly, a new section emphasizing a practical and simplified approach to GPIIb/IIIa antagonist therapy has been added.