Graphical user interfaces (GUI) provide interactive and intuitive visual communication to power system analysis application programs, enhancing the capabilities of engineers to conduct studies with ease and flexibility. As a result, since the late 1970s, a number of interactive graphical packages for power system analysis have been developed and are in widespread use. Object-oriented programming is gaining popularity, while the Windows environment is assuming a growing role in PC hardware platforms, due to its increased capabilities as a GUI environment. There are many different graphical packages for simulating, analyzing, and teaching power systems operations (built using such programming tools as C++, Object Pascal for Windows, or Visual Basic) that are the results of implementing object-oriented methodology in creating graphical user interfaces. This article focuses on possibilities offered by rapid application development (RAD) tools in building graphical user interfaces for Windows 3.X, Windows 95, and Windows NT platforms. RAD is a new way of programming that allows an application to be built interactively.