There is a necessity to model the Army Training Support System in order to improve its businesses practices and the overall decision-making process. Visualization has been chosen as a primary tool to represent the Training Support System of systems. The reasons for this approach are based on the complexity of the system. The TSS is so complex that it challenges the human capability to comprehend different interrelationships, activity flows and processes in an integrated way. New tools are needed in order to support the comprehension of such a complex system. The central idea is that, given the characteristics of human visual perception, human performance can be improved by providing displays that allow better use of the efficient processes of perception and pattern recognition. Additionally, the appropriate design of such tools will reduce the load of cognitively intensive processes of memory, integration and inference. Perception and cognition theories are used to provide a solid foundation in order to develop an effective visualization tool, which should minimize the perceptual processing load and free the mind for cognitive processes needed of managers and decision makers. Appropriate integration of concepts from complex systems, enterprise architecture, and human factors theories is being done to develop a methodology for building complex system visualization tools. This emerging methodology is based on the development of an integrated theoretical framework and the validation of such a framework by experimental findings.