This chapter outlines the epidemiology and risk factors for suicide as this provides the busy emergency department (ED) physician with a good framework around which to structure the patient interview. Knowledge about the risk factors related to suicide is important as it helps to guide the assessment of the suicidal patient in the ED. The risk of suicide is related to the type and severity of the psychiatric illness. In psychotic illnesses, such as schizophrenia, the risk for suicide can be especially high if the patient is experiencing command hallucinations telling the patient to kill him or herself. When assessing suicidal patients, it can be very helpful to have a framework to help recall the risk factors for suicide. The SADPERSONS scale is one tool that is commonly used as a helpful reminder in these situations. The immediate medical stabilization of patients following a suicide attempt is the first priority.