The development of a "good" information system relies heavily on the designer's (or project leader's) understanding of the system's boundaries and environment within the organization, and the ability to derive an appropriate model of the system. This report presents an overview of the systems appproach to organizational theory and information systems development, and examines one computer supported analysis and documentation tool, PSL/PSA. The report also shows that this tool, PSL/PSA, is not only able to represent such a systems view, but that it is also valuable as an aid, in terms of modeling, to other techniques which try to reach these goals. The examination of PSL/PSA is followed with two examples showing how it is applied to the BIAIT BICMX and Structured Analysis. / Thesis / Master of Science (MSc)