In spite of the great number of studies that have proved the existence of cognitive disturbances in schizophrenic subjects, conflicting results have not allowed to glimpse a typical pattern of neuropsychological deficits in schizophrenia. On the contrary, these results have raised important controversies regarding the nature of such cognitive impairment. Thus, questions concerning the existence of generalized versus focal cognitive impairment or in relation lo the static versus progressive nature of these deficits remain unresolved. In the middle of these debates, the need for prospective research, which focuses on the neuropsychological deficits of schizophrenia and other psychotic disorders from the beginning of the illness, has been pointed out. In these lines we present the results obtained in our study in which 59 subjects, who were admitted in our hospital for presenting a first psychotic episode, were assessed. Measures of premorbid adjustment, obstetric complications and clinical symptoms were taken and correlated to measures of cognitive performance obtained by using a minibattery of neuropsychological tests at time of dismissal. Results showed, as in previous research, that neuropsychological deficits are already present in psychotic patients at the beginning of the illness. These deficits in our sample were related lo obstetric complications especially in males, and disturbances of premorbid adjustment occurred in early stages of development. These results support the neurodevelopmental hypothesis of schizophrenia.