Various proposals have been made for new paradigms for operating the restructuring electrical system. One of the key challenges associated with this restructuring is to effectively analyze and evaluate the effects these alternative paradigms may have on major aspects of power system operations, including the so called ancillary services. This paper provides preliminary results on the development of a simulation tool to perform this analysis. Since power systems are ultimately governed by the laws of physics, the heart of the tool is a power system simulation engine, valid over a simulated time frame of minutes to days. The modular structure of the tool then allows other packages to be superimposed on this structure to represent different proposed paradigms. Integration of effective visualization into an interactive simulation environment is then used to gain understanding and insights concerning the attributes of each paradigm.