By increasingly complex and competitive business environment, the structure of an organization's departments plays a critical role in determining its overall efficiency and effectiveness in achieving tasks to investigates, how various departmental structures, ranging from functional to matrix models, influence task completion rates, employee satisfaction, and organizational agility. And analysing cases from diverse industries, the study identifies key factors that contribute to optimizing task achievement, such as clear role delineation, streamlined communication channels, and the alignment of departmental goals with overarching organizational objectives. It has been suggested that a well-designed departmental structure enhances task achievement by reducing redundancy, minimizing bottlenecks, and fostering collaboration across teams. Conversely, poorly structured departments can lead to inefficiencies, delays, and conflicts, ultimately hindering an organization's performance, that underscores the importance of continuous assessment and adaptation of departmental structures to meet evolving business needs. The researcher, in his research, advocates for a proactive approach to organizational design, encouraging leaders to regularly evaluate and refine their departmental issues.