The vitamin K antagonist, warfarin, is the most commonly prescribed oral anticoagulant. Use of warfarin is associated with an increase in systemic calcification, including in the coronary and peripheral vasculature. This increase in vascular calcification is due to inhibition of the enzyme matrix gamma-carboxyglutamate Gla protein (MGP). MGP is a vitamin K-dependent protein that ordinarily prevents systemic calcification by scavenging calcium phosphate in the tissues. Warfarin-induced systemic calcification can result in adverse clinical effects. In this review article, we highlight some of the key translational and clinical studies that associate warfarin with vascular calcification.