Summary: The pulmonary vasculitides are a heterogeneous group of primary or secondary diseases, in which there is inflammation that may lead to progressive destruction of the pulmonary microvasculature. Pulmonary involvement may develop because the lung has an extensive vascular and microvascular network, sensitizing antigens caneasily reach the lung, and there are large numbers of vasoactive and activated immune cells in the lung. Primary or isolated pulmonary vasculitis is extremely rare in children. Pulmonary vasculitis is an unusual condition in children and is almost always seen in conjunction with a systemic vasculitis syndrome. This chapter reviews common systemic vasculitides associated with pulmonary disease and discusses presentation, diagnosis, and therapy.