Dental health care workers are increasingly called upon to provide quality dental care to individuals whose bleeding and clotting mechanisms have been altered by inherited or acquired diseases. This provides an opportunity for the dentist who is trained in the recognition of oral and systemic signs of altered hemostasis to assist in the diagnosis of the underlying condition. A number of dental procedures result in the risk of bleeding that can have serious consequences, such as severe hemorrhage or possibly death, for the patient with a bleeding disorder. Safe dental care may require consultation with the patient's physician, systemic management, and dental treatment modifications.Of the inherited coagulopathies, von Willebrand's disease (vWD) is the most common. It results from deficiency of von Willebrand's factor (vWF) and affects about 0.8 to 1% of the population. 1 Hemophilia A, caused by coagulation factor (F) VIII deficiency, is the next most common, followed by hemophilia B, a F IX deficiency. The age-adjusted prevalence of hemophilia in six surveillance states in 1994 was 13.4 cases in 100,000 males (10.5 for hemophilia A and 2.9 for hemophilia B). 2 Application to the US population resulted in an estimated national prevalence of 13,320 cases of hemophilia A and 3,640 cases of hemophilia B, with an incidence rate of 1 per 5,032 live male births. Hemophilia A was predominant, accounting for 79% of all hemophiliacs, and prevalence of disease severity was 43% severe (< 1% F VIII), 26% moderate (1-5% F VIII), and 31% with mild (6-30% F VIII) disease. 2 Acquired coagulation disorders can result from drug actions or side effects, or underlying systemic disease. A stratified household sample of 4,163 community residents aged 65 years or older living in a five-county area of North Carolina revealed 51.7% to be taking one or more medications (aspirin, warfarin, dipyridamole, nonsteroidal anti-inflammatory drugs