"The Zodiac Killer 2023 Guide" focuses on the characteristics of the different crimes in which Zodiac is confirmed or suspected. Some unsolved homicides with Zodiac-like characteristics are included. Crimes for which Zodiac is no longer a suspect are provided as well. As the search for Zodiac victims has been centered on the general areas of San Francisco and Vallejo, the authors hope that this book will contribute to identifying overlooked victims in other regions.