SI:7 (aka or part of Stormwind Intelligence) is an Alliance organization. It includes rogues specializing in special operations, assassination, and stealth tactics. It is one of the most active organizations in the Alliance.
The guild is currently led by Master Mathias Shaw, grandson of Pathonia Shaw — the founder of a similar organization, the Stormwind Assassins, and a former master thief. SI:7 is located in the Old Town quarter of Stormwind. They have operatives all throughout the Eastern Kingdoms who carry out secret missions for Stormwind, such as Renzik "The Shiv" and Flint Shadowmore. They also have some operatives in the Kalimdor region, such as Andello Porter.
It is unknown if SI:1-SI:6 even existed, let alone what happened to them. SI:7 appears to be a clever reference to MI5 and MI6, the remaining sections of the British Directorate of Military Intelligence. SI:7's operations are similar to those of MI6 in that they deal with cloak-and-dagger external affairs. James Bond 007 is the service's most well-known fictitious agent.