Abstract: | This study aimed at investigating the association between employee-rated job insecurity and supervisor-rated adaptive performance. We hypothesized a nonlinear association between job insecurity and adaptive performance, expecting negative affect and negative work reflections to mediate this relationship. Using a sample of 131 employee–supervisor dyads, path analysis revealed a curvilinear relation between job insecurity and supervisor-rated adaptive performance, indicating medium job insecurity being linked to the lowest adaptive performance. Bootstrapping confirmed that negative affect and negative work reflection both mediated the nonlinear association between job insecurity and adaptive performance. After a time lag of 16 weeks, 71 supervisors again rated their employees’ adaptive performance. Path analysis confirmed a nonlinear association between employees’ job insecurity (T1) and supervisor-rated adaptive performance (T2). Theoretical and practical implications are discussed. |