Oral anticoagulant therapy with war farin is commonly used to prevent thromboembolic events in patients at risk. The degree of anticoagulation is variable among individuals and is influenced by many factors; therefore, patients must be monitored frequently to assess for potential adverse effects related to treatment. Individuals older than age 65 are at particular risk for thromboembolic events as well as anticoag ulant-related complications. Because of these factors, elderly individuals pose a unique challenge in maintain ing anticoagulant control. The purpose of this article is to revisit the role of warfarin therapy for elderly individ uals in the primary care setting and to provide nurse practitioners with the information necessary to prescribe and monitor this medication appropriately. This article provides indications for warfarin therapy and also identifies potential barriers to effective management with specific implications for the older population.