A brief historical review of intelligence work is followed by a discussion of the components of intelligence: collection, evaluation, and dissemination. A chapter on the intelligence unit addresses immediate investigations, long- range information packages, detailed studies, and the prediction of crime trends. A description of the collection and development of information sources focuses on the management of information collection, offense reports, witness statements, field interrogation cards, denunciations, letters, anonymous witness programs, searches, prison and parole reports, and outside intelligence reports. Other information sources are confessions and public records. Also discussed are the exploitation of information sources, the protection of a source, and ethics. Other chapters focus on informers, undercover officers, surveillance, information storage, evaluation, dissemination, security, organization and personnel, and organizational hazards. Glossary and 4 notes