Schizophrenic patients have a deficit syndrom which now is better known with new scales like the SANS of N. Andreasen and the PANSS of Kay. The dichotomy of schizophrenia in two kinds of disease--positive and negative schizophrenia--needs a critical review; but treatment of negative symptoms remains a real and difficult problem. Effects of antipsychotic medication (neuroleptics) on negative symptoms of schizophrenia have been hypothesized since 1958 by french psychiatrists: Broussole and Dubor. The main classifications of neuroleptics by Delay-Deniker, Bobon, Colonna-Petit have acknowleged the action that is called: antiautistic effect, antideficit effect or desinhibiting effect. This conception is a quasi specific position of french psychiatrists in opposition to most of the american psychiatrists who have thought during a long time that negative symptom did not respond, or poorly, to neuroleptics. The improvement of the methodology of clinical studies has made possible to confirm the clinical impression of an effect of some typical neuroleptics on negative symptoms: flupentixol, fluphenazine or pimozide. Moreover, a bipolar action of some NLP: desinhibition at low doses and sedative at higher doses has been individualised for some compounds: sulpiride, pipotiazine or amisulpride. Atypical neuroleptic like clozapine or risperidone also can reduce negative symptoms. Today we are not able to determine "the good desinhibiting NLP for the good schizophrenic patient"; so new studies are needed.