Abstract
Proactive career behaviors facilitate the transition from student to employee, and understanding the mechanisms behind their development is crucial for informing strategies that promote these behaviors. The literature indicates that the development of proactive career behaviors has been investigated in several studies; however, most of these studies employed a cross-sectional research methodology, thereby limiting the ability to draw robust causal inferences. This study is to investigate the mediating function of students' career adaptability in the relationship between psychological flexibility and proactive career behaviors throughout a longitudinal framework. The research involved 310 Turkish university students using convenience sampling. A two-wave cross-lagged panel model was tested within a structural equation modeling framework to examine cross-lagged effect among the variables over time. The findings indicated that students' career adaptability significantly mediated the longitudinal relationship between proactive career behaviors and psychological flexibility. It shows that interventions designed to enhance psychological flexibility and career adaptation within career counseling services can effectively boost students' proactive career behaviors. When assessed by human resources specialists, graduates with high psychological flexibility and career adaptability may exhibit more proactive and adaptable career behaviors, emphasizing the importance of including these attributes in recruitment processes.