From the Back Cover:
The Inner Sphere has been fighting a shadow war of clandestine intelligence operations for centuries, pitting House against House, agency against agency. In the war against the Clans, those same organizations cooperated to save worlds and keep hope alive on captured planets.
Now, something else is happening in the shadows. Mercenary units are disappearing without a trace. No one knows how to find them, or where to look. The governments of the Inner Sphere are helpless to move without the information that intelligence operatives provide.
The Intelligence Operations Handbook is a wolf net document detailing the operations of all the intelligence agencies of the Inner Sphere and Inner Sphere-based Clans. It includes the history and current activities of each organization and provides new archetypes and personal equipment suitable for use in any intelligence-based campaign.