Purpose Drawing on the conservation of resources theory, this study integrates an interactionist perspective with the process model of sustainable careers, thereby offering a comprehensive view of how personal and contextual factors jointly shape career outcomes. Design/methodology/approach A two-year longitudinal study with a three-wave time-lagged design was conducted to test a moderated mediation model linking perceived organizational support, work engagement, person–job (P–J fit) and indicators of career sustainability. Data were collected from a representative sample of 247 Dutch employees working across a variety of occupational categories in for-profit businesses or in non-profit or public sector organizations. Findings The findings show that contextual resources, such as perceived organizational support, do not automatically lead to career sustainability. Instead, we found that P–J fit functions as an enabling condition that determines whether resource gain processes can unfold. We therefore conclude that the interplay between person and context is not simply additive but that sustainable careers are shaped by individuals' ability to utilize them effectively. Originality/value This study contributes to the sustainable career literature by empirically demonstrating how perceived organizational support influences multiple indicators of career sustainability through work engagement over time. By integrating P–J fit as a boundary condition, this study advances the understanding of when and how organizational support fosters sustainable careers and offers actionable guidance for HR, including monitoring and enhancing fit and supporting employees in improving their alignment with their jobs.
Gürbüz et al. (2026) studied this question.