Like its predecessors, this edition concentrates on the origins of the names currently used for the cities, towns, settlements, mountains, and streams of California, with engrossing accounts of the history of their usage. It differs from its predecessors in three important ways:.

First, the dictionary has been updated to incorporate the latest research on California place names published by regional historians and to include new names that have been added to the California map since 1969, with particular reference to the current place name files of the U.S. Board on Geographic Names, a section of the U.S. Geological Survey. Second, particular attention has been given to local pronunciations of place names with unusual spellings.

Third, the many California place names of American Indian origin - such as Yreka, Shasta, Napa, Sonoma, Tamalpais, Yosemite, Coachella, or Poway - receive special coverage, based on recent fieldwork carried out by linguists and anthropologists among the California tribes. The book includes a Glossary and Bibliography that credits all the sources from which information has been obtained and indicates the resources available for readers who wish to do further research.