NATO Open Source Intelligence Handbook (Nov. 2001) (full-text).
This publication provides preliminary joint and coalition training information on the subject of Open Source Intelligence (OSINT). It discusses the fundamentals of OSINT support to both the all-source intelligence process, and to the unclassified intelligence requirements of operators, logisticians, and civilian organizations participating in joint and coalition operations. The focus is on relevant information that can be obtained legally and ethically from the public and private sector, and that is not classified in its origin or processing. The information may become classified in relation to the commander's intent or its association with classified information when it is rightly blended into all-source intelligence reports.