In addition to collecting and processing intelligence about our enemies and reporting to our consumers, the Intelligence Community is also faced with the problem of identifying, understanding, prioritizing and counteracting the intelligence threats (from foreign agents) that are faced by the United States. This activity is known as counterintelligence.
Counterintelligence involves more than simply the catching of spies (counterespionage). It is, in fact, concerned with understanding, and countering, all aspects of the intelligence operations of foreign nations. As defined in Executive Order 12333, counterintelligence includes both "information gathered" and "activities conducted" in order to "to protect against espionage, other intelligence activities, sabotage or assassinations conducted for or on behalf of foreign powers, organizations, or persons, or international terrorist activities, but not including personnel, physical, document or communications security programs."
The National Counterintelligence Executive (NCIX) serves as the head of national counterintelligence for the United States Government and provides strategic direction to the counterintelligence community.
An associated activity is the National Operations Security (OPSEC) Program - a means to identify, control, and protect unclassified information and evidence associated with U.S. national security programs and activities. If not protected, such information often provides an opportunity for exploitation by adversaries or competitors working against the interests of the US. An Interagency OPSEC Support Staff (IOSS) manages the program. Its primary mission is to act as a consultant to other US government departments and agencies, providing technical guidance and assistance that will result in self-sufficient OPSEC programs throughout government.