This thesis evaluates both the interface design process and the map- based mission planning tools of the Loosely Coupled Components Research Group, Naval Postgraduate School, for human factors usability. After identifying flaws in the process and usability problems in the interface designs, a new software design process and map-based mission-planning tool are developed. A usability study was conducted on the new mission-planning tool, determining it to be a usable product while establishing baseline data for future interface improvements. The map-based mission-planning tool, written in the Java programming language, is called the Mapping, Information, Display, and Analysis System (MIDAS). In its Beta form, MIDAS can display any geo-referenced map or image and allow users to annotate it with several graphical tools. Future versions will incorporate existing map-based decision-aiding tools such as optimal track routing, intelligence image rubber-sheeting, and wirelessly networked unit tracking. This thesis recommends the incorporation of human factors early in the software design process and quality usability studies on interfaces to ensure a usable product.