Discussing a book's appendices is a somewhat odd way to begin a book review. However, Appendix A in A Practical Guide to Groundwater and Solute Transport Modeling by Spitz and Moreno provides not only a concise overview of the steps involved in a groundwater modeling study, but also a good starting point to discuss why this text would be a valuable addition to a groundwater modeler's library. The general approach to modeling that Spitz and Moreno take can be found in many groundwater modeling books. However, one rarely finds a text that covers each step in the modeling process as well as this one does. This is especially true in three areas: the selection of model input data, the calibration of a model, and the development of model summaries.