In those situations, specific language constructs may be designed to help method practitioners organize, classify, and represent information that will later be synthesized into additional representation structures intended for display. With this foundation, language designers begin the process of deciding what needs to be expressed in the language and how it should be expressed. Language design can begin by developing a textual language capable of representing the full range of information to be addressed. Graphical language structures designed to display select portions of the textual language can then be developed. Alternatively, graphical language structures may evolve prior to, or in parallel with, the development of the textual language. The sequence of these activities largely depends on the degree of understanding of the language requirements held among language developers. These may become clear only after several iterations of both graphical and textual language design. Graphical language design begins by identifying a preliminary set of schematics and the purpose or goals of each in terms of where and how they will support the method application process. The central item of focus is determined for each schematic. For example, in experimenting with alternative graphical language designs for IDEF9, a Context Schematic was envisioned as a mechanism to classify the varying environmental contexts in which constraints may apply. The central focus of this schematic was the context. After deciding on the central focus for the schematic, additional information (concepts and relations) that should be captured or conveyed is identified. Up to this point in the language design process, the primary focus has been on the information that should be displayed in a given schematic to achieve the goals of the schematic. This is where the language designer must determine which items identified for possible inclusion in the schematic are amenable to graphical representation and will serve to keep the user focused on the desired information content. With this general understanding, previously developed graphical language structures are explored to identify potential reuse opportunities. While exploring candidate graphical language designs for emerging IDEF methods, a wide range of diagrams were identified and explored. Quite often, even some of the central concepts of a method will have no graphical language element in the method. For example, the IDEF1 Information Modeling method includes the notion of an entity but has no syntactic element for an entity in the graphical language.8. When the language designer decides that a syntactic element should be included for a method concept, candidate symbols are designed and evaluated. Throughout the graphical language design process, the language designer applies a number of guiding principles to assist in developing high quality designs. Among these, the language designer avoids overlapping concept classes or poorly defined ones. They also seek to establish intuitive mechanisms to convey the direction for reading the schematics.