Thanks to her background, she has a lot of pull with the upper echelons at CIRS. It's rumored that in the course of her work for the organization, she's come to learn the weaknesses of many of her fellow agents. This may have been a key factor in her "retirement" when the organization was restructured.

A report at this time detailing the gap between the American and Japanese intelligence services in terms of both efficacy and intelligence-gathering capabilities inspired Sengoku to create SORD (Social Ops, Research & Development); she then used her dismissal as an opportunity to establish herself, and SORD, as a leading force in tactical development.

(Source: Official site)