Patients with antiphospholipid syndrome are at increased risk for recurrent 
arterial and venous thrombosis and therefore benefit from long term warfarin 
therapy. The optimal duration of warfarin therapy after a first venous 
thromboembolic event is however a matter of some controversy and many questions 
remain unanswered. After reviewing and analysing the available evidence, we 
discuss some common scenarios in everyday clinical practice where treatment 
decisions are difficult.