"The practice of neurocritical care is sobering in one way and exhilarating in another. Perhaps the best demonstration of what we do,can do or should do to tip the scale is already in the Emergency Department, because acute neurologic disease typically is there seen first. There are numerous acute neurologic problems seen every day and so for emergency physicians the recognition of a serious neurologic disease must be an essential part of their expertise. Be that as it may, neurologists (and neurointensivists) are consulted freely because there is a sense that acute neurologic disease will worsen (and sometimes very quickly). In some patients the presenting emergency is already critical and unquestionably life-threatening. Acute neurologic conditions can appear anywhere in the hospital, but this chapter introduces the emergency department (ED), with all its complexities, as seen from a neurologist's perspective."