Many job redesign interventions are based on a 'multiple mediator/multiple outcome' model in which the job redesign intervention indirectly influences a broad range of employee outcomes by changing multiple job characteristics. As this model remains untested, the aim of this study is to test a 'multiple mediator/multiple outcome' model of job redesign. Multilevel analysis of data from a quasi-experimental job redesign intervention in a call centre confirmed the hypothesized model and showed that the job redesign intervention affected a broad range of employee outcomes (i.e., employee well-being, psychological contract fulfillment, and supervisor-rated job performance) through changes in two job characteristics (i.e., job control, feedback). The results provide further evidence for the efficacy and mechanisms of job redesign interventions. Key Words; job redesign, quasi-experiment, well-being, performance, psychological contract, call centre 3 Job redesign interventions are planned change initiatives that aim to modify job characteristics as a means of enhancing employee outcomes such as well-being and job performance (Parker & Wall, 1999;Semmer, 2006). Within the literature on job redesign, there is an increasing interest in understanding why job redesign interventions lead to successful outcomes (Biron, Karinka-Murray & Cooper, 2011). One approach to examining this issue has been to establish whether a change in job characteristics is the mechanism through which job redesign interventions have their effects. Specifically, studies have tested two models of this mediational process. The first is a 'single mediator/multiple outcome' model in which a job redesign intervention influences multiple types of employee outcome (e.g., affective, behavioral and attitudinal) through a change in one job characteristic, such as job control (Bond & Bunce, 2001;Bond, Flaxman & Bunce, 2008;Logan & Ganster, 2005). The second is a 'multiple mediator/single outcome' model in which a job design intervention influences one type of employee outcome (e.g., affect) by changing multiple job characteristics such as job control, feedback and participation (Holman, Axtell, Sprigg, Totterdell, & Wall, 2009).Many job redesign interventions are based on a 'multiple mediator/multiple outcome' model in which the job redesign intervention influences a broad range of employee outcomes by making changes to multiple job characteristics (Semmer, 2008). But this model of the job redesign process has not been tested, so there is little evidence for the efficacy of job redesign interventions based on it. Indeed, it is possible that intervention-induced changes to multiple job characteristics may only affect one type of employee outcome, or that changes to multiple outcomes might only occur when a single job characteristic is changed (Bond & Bunce, 2001).The main aim of this paper is therefore to test a 'multiple mediator/multiple outcome' model of 4 job redesign intervention by examining whether a job redesign intervention can enhance a range of...