Considerable research has explored the variables that affect the success of newcomer on-boarding, socialization, and retention. We build on this research by examining how newcomer socialization is affected by the degree to which newcomers’ peers and leaders provide them with positive feedback. We refer to newcomers’ perceptions of this feedback as “social validation.” This study examines the impact of social validation from peers and leaders on the development of organizational identification over time and the turnover attitudes of new employees. We found that perceptions of social validation significantly predicted how new employees used coping strategies to adapt to their new role over time, and consequently the development of identification and turnover intentions. Specifically, increased peer social validation predicted a greater use of positive coping strategies to engage with the new organization over time, and less use of disengagement coping strategies. In contrast, initial leader validation decreased newcomers’ disengagement from the organization over time. These results highlight the role of the social environment in the workplace in temporally shaping and validating newcomers’ adaptation efforts during transitions.