Heavy Work Investment (HWI) is a construct that comprises both workaholism and work engagement. We tested path analysis model on 364 Italian workers, with servant leadership as predictor of HWI Organizational Citizenship Behaviors (OCB) Counterproductive (CWB). also performed ANOVAs MANOVAs. Among the main findings, positive engagement OCB negative CWB. Conversely, workaholism, CWB, but it does...