The manual defines a computer-related crime expert, distinguishes among the various sources of experts, and discusses subject area specializations. Next, the question of when to employ an expert and considerations of case complexity and the individual law enforcement agency's philosophy and capabilities are presented. The manual reviews key phases in a computer-related crime investigation at which expert assistance will most likely be required. The major financial and professional considerations in selecting a particular expert or team of experts are detailed, as are general sources for identifying outside experts. The use of security precautions is examined and overall measures for avoiding and remedying breaches of security are suggested. Finally, techniques for managing experts throughout the course of a major case, with emphasis on the litigation stage, are presented. Tabular data and 56 references are provided. Appended materials include a discussion of significant issues in Federal expert witness law, a review of Federal pretrial and trial discovery issues applicable to computer-related crime cases, an annotated list of Federal and State cases regarding the use of expert witnesses, and a list of selected State privacy laws applicable to computer security.