In April 1980, members of the Democratic Revolutionary Movement for the Liberation of Arabistan took over an embassy at Princes Gate in London, England. The terrorists took 26 hostages in their quest to liberate the Iranian province of Arabistan.
Negotiators kept the terrorists' leader talking for three days, giving him media coverage of his demands (despite a botched reporting job by the BBC that sent him into a rage) and winning the release of two ill hostages. They earned his trust and got him to relax several deadlines. They also kept him focused on the micromanagement of small details, such as the type of bus he wanted, what kind of food to bring in and other minor matters.
Throughout the standoff, police were working to obtain intelligence about the inside of the building, a complex layout of offices. Information came from released hostages, food deliveries and cameras and microphones hung down chimneys or through walls.
Unfortunately, the terrorists executed one hostage (reportedly because he debated the merits of Islam with them), which forced British forces into action. They combined a carefully planned assault with a distraction provided by the negotiator. This was a breach of standard protocol -- usually, negotiators are not told when there is going to be an attack because it is too difficult for the negotiator to avoid giving anything away through tone of voice or choice of words. In this case, however, keeping the terrorist leader on the phone would keep him away from the windows, giving the troops some extra time to get into the building before the hostage-takers discovered the attack [ref].
The assault was a relative success. The terrorists killed one hostage when they realized they were under attack, and the remaining hostages escaped the building alive. British forces killed five terrorists during the assault, including the leader, and arrested the sixth.
For a complete account of the hostage situation at Princes Gate, see Operation Nimrod: The SAS Assault at Princes Gate.
In the next section, we'll find out how someone becomes a professional hostage negotiator.