The study describes the psychiatric disorders found in 100 HIV-positive patients, in different stages of the illness, at the psychiatric consultation service of a general hospital in Madrid. Eighty-five percent of the sample fell within the intravenous drug addicts risk group, which coincides with the epidemiological characteristics of Spain's HIV-positive population. The most frequently noted psychiatric diagnosis was substance dependence disorder (41%), followed by organic mental disorder (29%), adjustment disorder (15%), and affective disorder (5%). Fifteen percent of the subjects had depressive symptoms, and 11% expressed suicidal ideation. A follow-up conducted on part of the sample showed a development towards dementia, emphasizing diagnostic difficulties in the initial evaluation of these patients.