Vasculitis is an inflammatory process involving blood vessels. The term does not refer to one specific diagnosis. In fact, there are many different types of vasculitis. The conditions are often classified according to the type and size of blood vessel involved. Inflammation in the vessels may lead to narrowing, blockage, or even rupture of the blood vessels. The symptoms and clinical findings patients present with depend on where in the body this is taking place. Sometimes there is an identifiable trigger for the inflammation. At other times, the cause for the inflammation is unknown, but there are several well-described vasculitic syndromes where patterns of involvement and characteristic laboratory findings allow for a specific diagnosis. The rheumatologist can assist in arriving at the correct diagnosis and managing the disease, often with the use of immunosuppressive medications.