MANY DESCRIPTIONS of the phenomenon of denial of illness have been published.1The literature contains little, however, concerning the frequency of its occurrence. The purpose of this investigation was to determine the incidence of denial of illness in patients with hemiplegia. We chose hemiplegia because of its prevalence and extensive somatic involvement and for historical reasons. The study also permitted us to observe denial of illness in relation to the mental state of the patient, the side of the body involved, and other factors. The term anosognosia, introduced by Babinski in 1914,1ereferred to two cases of left hemiplegia, but it has subsequently been used by others to denote denial of other illnesses as well. Another phenomenon, the denial of existence of a part of the body, sometimes called autotopagnosia or somatoagnosia,1ghas at times been confused with anosognosia. For the sake of clarity, we decided to