Organizations often focus on bringing in newcomers with change-oriented tendencies, expertise and high status characteristics that can contribute to the improvement of organizational practices and products. However, in their effort to incorporate these newcomers in the organization and benefit from them, organizations assume that the onboarding process will be seamless, lacking insight on how this process unfolds. Drawing on the transactional model of stress, I propose that veteran peers are likely to perceive such newcomers as a threat to their self-view and their way of work. In addition, veteran peers’ contingent self-esteem on relative workplace performance and their satisfaction with the way of work will posit as boundary conditions. Finally, I expect that veteran peers’ threat perceptions will trigger negative behavioral reactions with important implications for both newcomers’ adjustment in the role and veteran peers work outcomes. A pilot study, interviewing veteran employees, was conducted to gain better insight of the phenomenon. Next, hypotheses were tested in a field study, surveying employees in three US organizations. Results from both studies are presented and discussed.