Several studies in schizophrenia found a positive association between cognitive performance and work status, and it has been reported that good cognitive performance at the outset does predict the success of vocational interventions. However little has been done to investigate whether vocational interventions itself benefit cognitive performance. To test this hypothesis we performed a randomized, placebo-controlled trial to investigate in remitted schizophrenic patients the effect of a 6-months vocational rehabilitation program on cognitive performance. We recruited 112 remitted and clinically stable schizophrenic patients who aimed to enter a vocational rehabilitation program. From these, 57 immediately entered a 6-months vocational rehabilitation program, whereas the remaining 55 were allocated to a waiting-list; the latter formed our control group, which received during the 6months out-clinic follow-up treatment. Before and after the 6-months period we assessed changes in cognitive performance through a neuropsychological test battery, as well as changes in the psychopathological status and in quality of life. We found that vocational rehabilitation significantly improved patients' performance in cognitive measures that assess executive functions (concept formation, shifting ability, flexibility, inhibitory control, and judgment and critics abilities). Moreover, after 6months the vocational group improved significantly in the negative symptoms and in quality of life, as compared to controls. Together with results from the literature, our findings reinforce the notion that the inclusion of vocational interventions may enhance the effectiveness of therapeutic strategies for schizophrenia patients.