Delays remain a persistent challenge in construction projects. This study presents a bibliometric analysis of academic literature published over the past two decades to identify the evolving focus areas in research on delay factors in construction. Using clustering techniques, six major thematic areas were identified: risks and risk management, project and construction management, design efficiency, cost control, performance challenges, and contract management. Findings reveal a recent shift in scholarly attention toward project and construction management and design efficiency, whereas earlier studies predominantly addressed risk and contract management. Moreover, the 25 most researched and cited keywords were represented using a Sankey diagram created with Python code. To validate these findings, an interview with an expert was conducted, offering practical insights into the relevance and applicability of the results. Overall, this research contributes to a practical understanding of critical delay factors in construction research areas and serves as a reference for both academic inquiry and professional practice.