Undated (AP) _ A glossary of some key terms used in the spy case against CIA officer Aldrich Hazen Ames and his wife, Maria Del Rosario Casas Ames:

-Counterintelligence: trying to stop foreign governments from penetrating your intelligence services. This is done by figuring out how other spy agencies are structured, what information they are targeting, who they are trying to recruit, and who in your own intelligence agencies might be double agents.

-Agent: someone who clandestinely and illegally acts on behalf of a foreign intelligence service - other than an officer or other employee of that service. Ames allegedly was acting as an agent for the Russian government.

-Mole: an official inside an intelligence agency who illegally reports to foreign governments.

-Operations officer: in the CIA, an employee who handles or ''runs'' an agent. It is the agent, not the officer, who does the actual spying. Ames was an operations officer during at least part of his career abroad.

-Dead drops: a prearranged location where an intelligence officer and a foreign agent can communicate clandestinely to transfer documents or other objects. An agent may hand off a computer disk, for example, by placing it in a trash bag and then hiding the bag in a log or a pipe. The officer who is handling that agent would retrieve the bag without being in contact with the agent.

-Russian intelligence: the Russian foreign intelligence service, commonly referred to by U.S. intelligence agencies as the SVRR. It is the direct successor to the Committee for State Security of the USSR, commonly known as the KGB.