Parasol is a python framework in which mathematical models can be investigated parametrically. Parasol enables easy optimization, sensitivity study, and visualization. The math model can be as big or as small as desired. Output is generated in plain text, HTML, and native Microsoft Suite files (Excel, Word and PowerPoint). A problem is defined by input and output parameters. Results are presented in a manner that conveys insight into system trends and characteristics. The process of performing an analysis results in an ample assortment of graphs, charts, and images that display system sensitivities, variations, and characteristics. Barriers to creating these displays have been reduced to single commands in order to facilitate their use. Parasol has been designed to run under Microsoft Windows. Home Page: http://pyparasol.sourceforge.net/