<![CDATA[Improving employee performance requires strengthening competencies through training, human resource development (HRD), and adaptive capability, particularly in responding to changing job demands and dynamic organizational environments. This study aims to analyze and prove the individual (partial) and joint (simultaneous) effects of training, HRD, and adaptive capability on employee performance. Employing a quantitative approach, this research was conducted at the Regional Office of the Ministry of Transportation, South Sumatra (Class IIA). The population comprised all public sector personnel, with a sample of 120 employees selected through purposive sampling based on length of service and prior participation in training or development programs. Data consisted of primary and secondary sources collected via structured questionnaires, observations, and documentation. Multiple linear regression analysis was executed alongside validity, reliability, classical assumption, t-tests, F-tests, and coefficient of determination (R2) evaluations. The findings reveal that training, HRD, and adaptive capability exert positive and statistically significant effects on employee performance both partially and simultaneously. HRD demonstrates the most dominant influence with a standardized beta coefficient of 0.393, followed by training (β=0.306) and adaptive capability (β=0.172). Concurrently, the three variables account for 31.2% of the variance in employee performance (R2=0.312; F=17.531; p= 0.000). The novelty of this research lies in the tripartite conceptual integration of short-term operational skill building (training), long-term career and character building (HRD), and psychological-operational flexibility (adaptive capability) within a unified empirical model. By evaluating these constructs simultaneously within a regional public transportation authority, this study bridges prior empirical inconsistencies where isolated HR interventions yielded non-significant results. It demonstrates the systemic complementarity required to sustain public servant performance amid regulatory and digital disruptions. Managerial implications highlight the necessity of integrating needs-based technical training, continuous career development, and organizational cultivation of adaptive capabilities as a strategic policy framework to optimize public service performance..]]>
