This book is about investigating prison gang crimes—the crimes gang members commit for the benefit of, at the direction of, and in association, with the specific intent to promote, further, and assist their criminal street gang. A story told by me, a retired experienced California gang investigator who has testified in San Joaquin County court nine (9) times as a gang expert. Come on this exciting journey and learn how to investigate prison crimes, what to do when you arrive at a crime scene, and some tactics on how to determine who is involved. How to talk and communicate with the gangsters. How to collect evidence, DNA, photograph, interview, document, Miranda Admonishment, how to set up a Simmons Lineup, and prepare your case for the Deputy District Attorney. Learn how to prepare a gang write-up, a Curriculum Vitae and how to testify in court as a gang investigator.