The Office of Military Intelligence (OMI) is the Sioux Nation's intelligence agency. While it typically focuses on intelligence efforts on the UCAS and CAS, it is known to have agents in other NAN states. It also watches megacorps involved in Sioux affairs.
In early 2050s, OMI director responsible for all of that was Sheila Wolffriend ("Wolf") tried to turn OMI into a personal empire and spectacularly failed. OMI failures from around late 2053 included involvement in a run that almost caused a global war (eee Shadowplay). Wolf disappeared around late 2053, while OMI was restructured (and significantly weakened). In 2054, the OMI went through a series of embarrassing disclosures that revealed the organization to be a failure on many accounts. The organization was purged, and Sinopa - of whom very little is known - took the helm.
Sinopa changed the organization to also handle counter-intelligence and internal security, effectively putting surveillance on the entire Sioux Nation population for national security.