The mental status examination is an interview method psychiatrists use to gather and organize their observations about the patient's mental functioning. The mental status examination in psychosis and near psychosis involves the careful examination and exact description of ego functions. This chapter focuses especially on aspects of ego structure that define psychosis and near psychosis. It describes the mental status examination of those aspects of ego function crucial to the organization of psychosis and near psychosis. The mental status examination is an active inquiry with patients about their mental experience. The boundary between outside and inside is easily observed in the mental status examination. Because thing presentation experience dominates the very ill patient's mental life, observation and inquiry about this are important in the mental status examination. Thus the mental status procedures of observation, active inquiry, and beginning descriptive interpretation hold for lack of integrations just as they hold for other mental phenomena that emerge.