In an effort to illustrate these principles it is useful to examine both a simple hypothetical aquifer system as well as a groundwater development case. Development of a simulation model for a simplified hypothetical problem offers the advantage of having control over the system and complete knowledge and definition of hydraulic properties and boundary conditions. For an illustrative example of a well-documented field problem, we look to the United States Geological Survey (USGS) Regional Aquifer System Analyses (RASA) studies. As part of one RASA study, an agricultural development in Paradise Valley, Nevada, USA, was studied in detail. We review the highlights and lessons of this study, which illustrate how the principles of development are applied to a complex system.