Essential Guide to USMC CI & HUMINT Operations This is the latest revision of the USMC Counterintelligence (CI) and Human Intelligence (HUMINT) manual, just released in February 2025 . Designed as a foundational reference, it provides valuable insight into intelligence operations while remaining fully unclassified and accessible to the public. Whether you're a military professional, researcher, or simply interested in intelligence doctrine, this manual is a must-have. Newest Edition – February 2025 – Stay up to date with the most recent revision of this official USMC training manual. Unclassified & Available to Citizens – No restrictions—this guide is fully accessible to anyone interested in military intelligence principles. Covers CI & HUMINT Fundamentals – Learn about operations, planning, security, command structures, and training in intelligence support. Authentic Military Reference – This is a direct republication of the official Marine Corps manual, preserving its original content. Great for Training & Study – A valuable resource for military personnel, researchers, historians, and those interested in intelligence operations. (This manual has been professionally bound into book form to provide a durable and accessible reference for the reader’s convenience. All content remains unchanged from the original publicly available document.)