This chapter describes a methodology developed to elicit knowledge for the design of a corporate Intranet within a government agency. This Intranet was intended to supply knowledge management systems solutions to various problems such as work duplication, document location, and accessing tacit expertise that was distributed across different office locations and departments. An inventory of the pertinent knowledge was required. We situate our discussion of this undertaking within the context of ontology and what it means for something to be a depiction of a socially constructed reality, a representation of the knowledge of a group. We developed a methodology combining soft systems methodology, causal cognitive mapping, and brainstorming to create a knowledge ontology using UML class diagrams. The methodology offers an effective approach for understanding nonroutine yet rigorous knowledge work and conveying relevant and contextual knowledge to the designers of solutions.