Essential Strategies, Inc. was hired to develop an enterprise conceptual model for a Canadian Provincial highway department. The model made extensive use of ESI's patterns, but it did require specialized attention in defining just what a road is. It is a very different thing, depending on whether it is percieved by a lost motorist (who sees it as a line), a highway planner (who sees it as a right-of-way area), or maintenance personnel (who see it as a solid, consisting of concrete, asphalt, and such materials). The model of a highway interchange was also very interesting.