The number of patients referred to hospital clinics for monitoring of oral anticoagulation continues to rise rapidly. Introduction of computer programs for the control of oral anticoagulation improves the quality of anticoagulant control in hospital clinics. This approach has now been extended to include patients managed in general practice. Results confirm that the quality of anticoagulation can also be improved in these patients. A standard approach to anticoagulation for hospital and community based patients has also facilitated the transfer of patients on warfarin from the hospital anticoagulant clinics to the community with no deterioration in the quality of anticoagulant control. As a result, the workload in the hospital anticoagulant clinic has fallen for the first time.