As the use of online business systems increase so does the need to produce more efficient and less error prone web based Modeling is a core abstraction mechanism used to manage complexity, drive implementation and save resources by facilitating the identification of potential problems during systems design. While there is a prevailing intuition of the benefits of using modeling languages such as the Unified Modeling Language (UML) in the development of very large systems, research is needed to delineate the viability of modeling languages for small and medium sized applications. This paper reports on a case study that examined the viability of using UML to model web based applications that require 20 - 50 hours to produce for developers new to UML. The goal of the research is to answer three questions. What are the benefits and costs of using UML diagrams? Will UML diagrams increase the customers understanding of the applications being developed? Will UML diagrams decrease error prone...