This chapter deals with the occasionally seen complaint of acute expectoration of blood/blood-stained sputum for which a patient may present to the Emergency Department. Methods to ascertain the source of bleeding both by a proper history and by detailed clinical examination and endoscopy are described in detail. Differential diagnoses for this particular complaint are listed for a quick reference. The chapter is amply illustrated with clinical pictures. The need for digital subtraction angiography in cases where a vascular abnormality is suspected is described. Based on the site and severity of bleeding a number of measures have been described to treat the episode.