Acknowledging the evolving composition of modern workforces and nature of contemporary work, we offer a review and research agenda for integrating diversity process theory into career and vocational behavior research. Based on a review of theories that articulate how social identity shapes career outcomes, we highlight a need for additional theorizing that captures the dynamism and complexity of human experience and intersecting roles embedded within the career lifecycle. To address this need, we propose approaching the study of vocational behavior from a diversity process perspective. Integrating three diversity-related processes (identity, information processing, inclusion) across three career stages (career choice, adjustment, exit), we develop a model for exploring how diversity influences people's career experiences and transitions. Specifically, we identify five career transitions – identity-choice, information processing-choice, information processing-adjustment, inclusion-adjustment, and inclusion-exit – and discuss the underlying mechanisms for each. We also suggest specific directions for future research that respond to the increasing diversity and intersectionality of modern workforces and advances foundational insights into how individuals navigate their career experiences and trajectories. By bridging the gap between the career and diversity theoretical domains and offering a new perspective for researchers and practitioners in the field of career development, we hope to take an important step toward a more comprehensive, inclusive and socially responsive understanding of vocational behavior.