Thromboembolic events with partially or completely persisting neurologic deficits are reported in a substantial number of patients after endovascular aneurysm therapy. The authors discuss the current status of periinterventional coagulation management in endovascular aneurysm therapy. First, some basic aspects of coagulation physiology relevant to neurointerventions are introduced. Second, the most important pharmacological aspects of heparin, protamine sulfate, low-molecular-weight heparin, tissue plasminogen activator, acetylsalicylic acid, clopidogrel, abciximab, tirofiban and eptifibatide for neurointerventions are considered. Third, the use of these drugs in periinterventional coagulation management are discussed with special emphasis on current standards in anticoagulation/antiplatelet strategy and their impact on aneurysm perforation rates. Moreover, treatment of thrombotic complications of endovascular therapy of cerebral aneurysms is discussed.