This article does not cite any sources. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (December 2009) (Learn how and when to remove this template message)

The International Security Alliance (ISA) is a fictional spy agency on the soap opera Days of Our Lives. A highly secretive organization, its agents have been operating in the Midwestern town of Salem at least since its first appearance on the show in the early 1980s (although several characters' histories indicate involvement well back into the mid-to-late 1970s).

Several of Salem's more recognizable citizens have served at one time or another as agents for the ISA, including Roman Brady, John Black, Billie Reed, Steve Johnson, and Rafe Hernandez. Agents formerly on the show include Philip Kiriakis, Shane Donovan, and Bo Brady.

The agency was originally conceived as an unnamed multinational crime-fighting task force, well-funded but relatively informal and highly secretive, with agents and operations all over the world. As time progressed, the ISA was given a name and fleshed out into a full-fledged government agency, made up of mostly British and American agents. It was originally unclear what national (or supranational) government the ISA reported to, and although it became a more formalized intelligence or "spy" agency, the ISA's focus generally continued to center on criminal investigation rather than political espionage. The agency has tended to specialize in the sort of high-level, international criminal conspiracies that has tended to center in the otherwise quiet town of Salem -- such as those controlled by the DiMera, Kiriakis, and Alamain families.

In more recent years, the show's writers have presented the ISA as a U.S. government intelligence agency, but with a somewhat muddled (and unrealistic) mission--the criminal investigation mandate of an Interpol or FBI combined with the methodology of a CIA or military "black ops", with some actions coming straight out of Robert Ludlum or Ian Fleming, including sophisticated gadgets, top-secret operations, and even such questionable methods as kidnapping, blackmail, corruption, and assassination. The organization works fairly openly with local police, "undercover" agents readily identify themselves as ISA members, and they have legal powers of arrest in their own right. The ISA also has several advanced scientific and medical facilities throughout the world, dealing with problems encountered by its agents such as brainwashing and biological warfare.

Along with blurring the real-world lines between law enforcement and espionage, the ISA appears to operate with impunity throughout the world and across jurisdictional lines, but does not appear to take sides in any real-world political controversy of the day. However effective it may be, the agency also appears to be highly susceptible to infiltration, counterespionage, and corruption by its targets. The agency has also experienced both partnerships and conflicts with real-life agencies such as the FBI and the CIA.

Directors (or "Chiefs") of the ISA depicted on the show have included George Nickerson, Ogden Vaughn, "Chief" Tarrington, and most recently, Pamela Van Damme. None of these officials have shied away from unsavory actions to meet their objectives, and most (except Tarrington) have proven to be outright corrupt, if not psychotic. In fact, the agency itself occasionally finds itself acting as badly (or worse) than the organizations it is battling.