SIS was founded by former US Green Beret Graham Chaplain, a man frustrated that his expertise was being wasted by the government on mundane peacekeeping operations in the Middle East. Once news of Odessa's bombing reached their firebase, he was contacted shortly after by a Towerlight operative offering him a lucrative job. Seeing a potential and rather lucrative way out, he quickly signed on. He was given the task of starting a security corporation to protect and advance the interests of Towerlight and her allies throughout the globe.
The trademark quality of SIS contractors are the armor that each contractor is assigned. The concept is simple: take the reactive armor that protects many tanks today and miniaturize it so that it can protect an individual man. The armor comes hermetically sealed with a 30 minute supply of oxygen before switching over to an ABEK-HgP3 filter. SIS is still a rather small operation, but this allows them to train each contractor to a much higher skill level than average (about equivalent to an experienced US Army Ranger, if not higher). This lower troop number has also allowed SIS to purchase a handful of prototype V-280 Valor helicopters (very similar to the Ospreys the US Marines currently use) as well as several Little Birds and Humvees.
The majority of SIS troops remain within the continental US, but a handful are stationed near Odessa to assist 'Towerlight forces control the area.