The accelerated pace of globalization necessitates that civil engineering graduates possess a broad spectrum of competencies to meet the evolving needs of a dynamic, interconnected professional environment. This necessity encompasses a blend of practical, personal, and intercultural skills in aspiring engineers, driven by employers' increasing demand for multifaceted skill sets. International research experiences are pivotal in bridging the gap between traditional academic training and the complexities of the real world, offering substantial benefits in terms of personal growth, intercultural understanding, and enhanced research innovation through exposure to diverse methodologies and global professional networks. Despite these advantages and the critical need for engineers adept at navigating the global landscape, participation in international programs remains markedly low among civil engineering graduates, underlining an urgent need for increased engagement and methodological research to elucidate the immediate and long-term benefits of such experiences. This dissertation critically assesses the effects of international research experience on developing key competencies of graduate students, including personal, academic, and professional development, intellectual growth, and intercultural competence. Recognizing the scarcity of rigorous, empirical studies capturing the comprehensive benefits of abroad research, this study adopts a mixed-methods approach, combining quantitative surveys with qualitative interviews to enhance the validity and reliability of findings through data triangulation. Additionally, data collection occurs at multiple time points before and after the experience, providing an in-depth exploration of how such experiences contribute not only to immediate skill enhancement but also to sustained competence development. The research addresses a critical gap in the existing literature, providing evidence-based insights into the multifaceted value and transformative potential of these experiences on graduate engineering competence advancement. The findings indicate improvements in academic proficiency, marked by adopting innovative research techniques and professional capabilities through expanded networks and enhanced communication skills. Moreover, immersion in international settings elevated students' self-reliance and global consciousness, alongside fostering comprehensive growth in intercultural understanding, thereby contributing to their holistic development across personal, intellectual, and professional domains. Through this comprehensive analysis, the study aims to offer actionable recommendations for designing and evaluating future research programs abroad to foster engineering graduates with the advanced competencies required to tackle contemporary challenges and flourish in the global environment.