Expert consensus on sustainable employability of older workers: research, practice, and policy dimensions.

Introduction: Sustainable employability has been recognized as a central construct for understanding workers' continued participation in the labor market throughout the life course, particularly in the context of population aging, technological transformations, and changing work arrangements. Despite growing research in this field, conceptual fragmentation and a lack of consensus persist regarding the key factors, organizational practices, and public policies associated with the construct. Accordingly, this study aimed to identify factors, organizational practices, public policies, and research dimensions related to the sustainable employability of older workers from the perspective of international academic experts. Methods: A sequential exploratory mixed-method Delphi design was adopted. Fourteen experts from different countries participated in the first Delphi round, with 12 completing the second round and 9 completing the final round. The first qualitative stage was conducted as a structured elicitation exercise and organized participants' responses into five analytical domains: the definition of sustainable employability, organizational practices, public policies, individual factors, and research dimensions. In the subsequent rounds, the items derived from these domains were quantitatively evaluated for expert agreement. Results: High levels of consensus were observed regarding physical and mental health, lifelong learning, healthy work environments, organizational practices to combat ageism, workplace flexibility, and the integration of health, social security, and employment policies. Additional dimensions, including meaning of work, career adaptability, work-life balance, and support networks, also achieved the predefined consensus criteria in the final Delphi round. Divergence remained primarily for selected policy-related dimensions, particularly tax incentives for companies and funding for age-friendly workplace adaptations. Discussion: The findings support the conceptualization of sustainable employability as a multilevel and contextual construct encompassing individual resources, organizational practices, and institutional policies. This study contributes to the conceptual advancement of the field by providing expert-based evidence that clarifies the construct and identifies dimensions that achieved expert consensus, thereby informing future research, organizational practice, and public policy.